Authenticated Multicast Immune to Denial-of-Service Attack* Shouhuai Xu Ravi Sandhu Laboratory for Information Security Technology SingleSignOn.Net, Inc. Reston, VA, USA George Mason University and MSN 4A4, University Dr., Fairfax, VA 22030, USA George Mason University, Fairfax, VA, USA sxul @ gmu.edu sandhu @ gmu.edu ABSTRACT Authentication of multicast streams has attracted a lot of at- tention in the last few years.

two important issues, namely multicast denial-of-service and access control, have been ignored in previous proposals.


We chose this speci.c construction to allow for relatively compact SEALs, while the longer salts mitigate attacks to .nd other pre-images for the SEALs by pre-computation.

if the SEALs are long enough to prevent such attacks, the one-way salt chain may not be necessary.


It had been thought that if S-boxes are kept in secret, one can consider them as additional parts of the key.

it has been demonstrated in [5] that particular values of S-boxes used for encryption can be reconstructed quite easily.


To accommodate such legitimate operations, we use the aforementioned mechanism to make chat messages visible only in the context of the subject app (e.g., Go SMS).

the detector denies all updating requests on the address, body and uid columns of the sms table in the database.


This is one of the classic usable security problems, which leads to users ignoring, misusing, or even subverting the security warnings.

there are other, and more subtle, problems that result from automation failures in which users must be responsible for deciding the correct course of action.


5.7 Limitations Our work only examined high-pro.le IdPs and the 96 RPs in English that we found in the top 1,000 most-visited sites, and hence the evaluation results might not be generalizable to all IdPs and RPs.

our statistical analysis did not reveal any correlation between websites popularity rankings and the discovered vulnerabilities.


Issues of privacy can 73 also be tackled by the use of trusted third parties to mediate the exchange of information.

it can be difficult to get everyone in a community to agree on a suitable third party, particularly when new users continually enter the system and live in different jurisdictions.


Since access control requires the consumer to send authentication and authorization information to the producer, it is practically done when the client subscribes.

since following interactions are only one way messages, authorization of the subscriber cannot be veri.ed.


The primary goal of SSL is to provide privacy and reliability between two communicating applications.

the SSL protocol, as it is currently being used on the World Wide Web can be subverted [g].


More seriously, given reliable delivery noti.cation, a process could leak information using careful label changes, for example causing successful delivery to correspond to 1 bits and unsuccessful delivery to 0 bits.

since only label checks (and resource exhaustion) will cause messages to be dropped, careful compartment management such as our Web server s can make delivery reliable in practice.


The distribution of values in the synthetic rulesets is very close to the uniform distribution.

the distribution for the real rulesets is much more interesting from the point of resulting bit ordering for the construction ofthetree.


The most interesting property of this construction is that it meets property 4 in that puzzles challenges can be made from a random beacon.

it does not meet property 3, so the client must compute puzzle solutions particular to the server it is contacting.


Live digital forensics tries to take a snapshot of the computer state, similar to taking a photo of the crime scene.

since computer systems are dynamic, the processes and connections are continually changing, bu.ers are .ushed to the disk periodically, and the snapshot may not re.ect the true state of digital crimes.


The current version of CREST yields signatures based on this exploit string.

we are now working on a more advanced implementation of CREST, in which we attempt to isolate exactly the (minimal) part of the network trace that causes the exploit.


The simplest solution to this problem is to use on-line e-cash: the seller consults the bank during every transaction to ensure the promised e-coin is new.

this approach places a heavy burden on the bank and compromises the privacy of the user (if a fair exchange fails, new e-coins can be linked to old ones), and thus is not preferable.


Similarly, the .rst execution of a program that decrypts e(m) will traverse the states q0,...,qj ,qj+1, where qj+1 is the state that results from a successful decryption.

returning the machine to its initial state q0, using the same instructions r, the state traversal will be q0,...,qj ,q j' +1 .qj+1, = because the decryption fails.


Note also that with each query we can only get up to 5000 user ids.

we find that generally one single request is sufficient to download the complete list of friends.


Our problem is also related to the problem of policy composition [35].

work in the area of policy composition typically only considers how policies of the same type can be combined.


Doing so requires a significant infrastructure to map between human-readable names and integer IDs.

integer IDs offer the simplicity of dealing with fixed-size numbers, and guaranteed uniqueness over time.


We consider this an important facility as many applications expect directories to be available.

it can be observed that the ability to read directory contents is not required in a signi.cant number of usage scenarios we are targeting with VPFS.


As general purpose functions like MD5 or SHA1 were designed to be fast and e.cient, they serve in favor of the attacker who wants to compute a large number of digests in a short amount of time.

adaptive hash functions, such as bcrypt [48] and scrypt [47], can be con.gured in terms of the work factor they introduce.


Ideally they should be scheduled together optimally so that a superscalar processor can efficiently exploit the higher instruction level parallelism embedded in the code.

this requires secret sharing code to be inlined first, which leads to code explosion.


In Dalvik, the maximum stack size is 256KB (plus a 768B region for handling stack over.ow errors).


Figure 2: Building trust in SMI handler Note that the hypervisor is also measured during trusted boot.

the trust in the hypervisor cannot be sustained due to its interaction with potential attackers.


Although we believe we have covered all the features of the applications, it is possible we had somehow missed a feature that was not obviously accessible in the GUI.

since any overlooked feature was not obviously accessible, it is probably not frequently needed by users.


Among all the related work we have discussed earlier, the attack reported in [9] on a MegaUpload CAPTCHA is the only one that has a slight similarity to our attack.

that attack was designed for a single CAPTCHA; it is ad hoc and not applicable to attacking hollow CAPTCHAs.


For instance, in the case of SpamBayes, the mistakes SpamBayes makes maycause the user to speci.cally identify and retrain on attack messages when these messages appear with his normal mail.

most users are less likely to notice messages that inadvertently mislabeled as spam.


The in-component vulnerable paths are relatively common and have been the subject of recent studies [24, 34].

the latter two, especially the cross-app ones, have not been well studied yet, which is thus the main focus of our re.ection analysis.


LPRNG depends on external sources for randomness: utsname, ktime, and various device events, which are transferred by input_pool.

an Android device has no user inputs such as a mouse or a keyboard, and has a few interrupts until Zygote is launched at the system boot.


A host can be reached either via name or real IP address (rIP).

only authorized entities such as administrators are allowed to communicate with a host via rIP.


On the other hand, scenario sets b) and c) might appear a bit unusual because they use more than one .ngerprint scanner for authentication.

our aim is to investigate how performances of these scenarios are compared to each other.


There are many constructions of leakage-resilient primitives in this model, including stream ciphers, symmetric key encryption, signatures, public key encryption, and identity-based encryption [1, 2, 3, 11, 15, 33, 41].

assuming that leakage is bounded throughout the lifetime of the system seems unrealistic, since there is no bound a priori on the number of computations that will be performed.


INTRODUCTION Password-based authentication is considered to be the most popular method of user authentication, mainly because of its simplicity and cost e.ectiveness.

it is by no means a panacea as far as usability is concerned.


Thus far our work has focused on snapshots of paused systems.

we have experimented with extraction of information from live operating system structures, such as being able to monitor process creation and destruction in real-time.


3.3 Randomized Spanning Trees An obvious approach to performing the mapping would be to compute general graph isomorphism between the contact and social network graphs.

general graph isomorphism is an NP-hard problem, so this approach would be computationally intractable for large contact graphs and social networks.


The .rst approach at such a positive security result was taken for the WS-Federation Passive Requestor Interop (WSFPI), a Browser/POST pro.le of WS-Federation, in [11].

this proof is built on top-down assumptions about the participating parties, i.e., assumptions made to suit the speci.c proof, in particular the browser and user, and not on a detailed, reusable model of these parties.


During the active periods, they follow the same set of users at around the same time.

normal users exhibit diverse user-following behavior.


The penalty is higher for the other hash table types, as we can t know how many uniquekeysfall into anygivenbucket until the cuckoo tables arebuilt.Ifabucketfailstobuildits tables,the whole process must restart from Phase 1.

the chance of this happening decreases as multiplicity increases: because the amount ofbuckets allocatedis dependentonthe total numberof itemsand notthe numberof uniquekeys,it becomes moredif.culttoover.ll abucket.


Indeed, all the highlighted roles can be played by di.erent entities, thus enabling a rich and .exible environment for requesting and receiving Assertions.

sAML does mandate that the processing of the AuthnRequest must be based on an existing or new Authentication context, and the resulting Assertion contain at least one AuthnStatement.


There are certain separation of duty constraints that could be hard-wired into the application no user can be assigned to both the purchase order clerk and .nance clerk roles, for example.

there are certain separation of duty constraints that can only be speci.ed by the administrators of a particular installation of that application.


If the PC is implemented as a stand-alone module that only needs to communicate with the user s device to operate, then the user s device can be less powerful (more on this below).

the bottom line is that user computing devices that are insufficient in computing power (e.g.


Furthermore, the cooperating server policy extension mitigates this problem.

the protection o.ered by the server-side extension depends on the serverpolicywriter by relaxing the client-side policy, the server policy is able to reduce the amount of false positives, but it is also able to introduce false negatives if this relaxation is pushed too far.


As a result, we observe orders of magnitude fewer instances compared to automated hijacking.

criminals heavily abuse victim s information, making such attacks highly distressing to the impacted parties [22].


The link between this subject and the second message would not be derivable from a single concept.

this a.ects just transitive linkability threats which arise from relations with one or more intermediate item.


When using class loader DexClassLoader in Dalvik, the protected method loadClass() in Dalvik does check whether the class is already loaded or not; if it is, it will not reload the same class.

this is only enforced inside DexClass-Loader, so if a malicious component extends DexClassLoader and overrides loadClass(), it can successfully reload a class.


TESTING 3.1 Problems Encountered ITSG encountered several problems during the testing of PGP Desktop 9.9 in the existing departmental Universal Server environment.

all of these problems were related to a lack of documentation on the specific limitations or functions of the Macintosh client feature set, as opposed to technical problems.


Another possibility is that A knows this address from previous communication rounds.

both devices do not share a (symmetric) key.


Conflicts high integrity subject-permission subject-permission assignments assignments Figure 4: Assignments lead to con.icts and those that lead to the most con.icts have the highest potential impact for resolution.

other assignments may overlap thus reducing the base impact of one con.ict.


Such smart access capabilities enable owners to remotely monitor and operate their devices using phones, tablets, or through designated websites.

smart meters are designed to receive realtime electricity pricing (RTP) and pass on to household devices [14], which optimizes energy consumptions based on RTP [34].


4.1 A Binary Feature Space Mapping consumption traces to a vector space may seem trivial at a .rst glance, as the measurements of a day are already represented as a d-dimensional vector.

for discriminating di.erent patterns in this data, we require a more advanced representation that emphasizes the characteristics of each consumer and provides an expressive basis for application of machine learning.


Under these circumstances problems of the improving information management systems in all spheres of society s activity come to the forefront of economic and social development and intensive and large-scale research in recent years.

the information society development leads to an increase of threats to national and international security related to violation of the established modes of ICT systems usage, infringement of the constitutional rights and freedoms of citizens, malware spread as well as the use of modern IT in hostile, terrorist and other criminal acts.


To expose these behavioral similarities, malware binaries are usually executed in a monitored sandbox environment, in order to identify malware families characterized by similar host-level events [e.g., 1, 3, 20, 27] or network tra.c patterns [e.g., 13, 14, 24, 25].

regardless the behavioral features being used, all these proposals su.er from the same vulnerability: clustering algorithms have not been originally devised to deal with data from an adversary.


Approaches that passively monitor various security properties have been proposed [10, 11, 13, 19].

passive monitoring can only detect remnants of an already successful attack.


This is handled as follows: The parties will only choose the new hash function after the previous HH was sent over the channel, so in order to create a collision, the adversary must change the hash function (rather than its input).

if the adversary created errors in the hash function, then the states of the two parties will di.er since one of them received the wrong description of the hash function (while the party who generated the hash function of course has the correct value).


Constructing the behavior .ngerprint requires roughly the same computational resources for all methods.

the Bloom .lter based methods, because they use the same .xed amount of storage for all time windows, require a constant number of operations when performing the .ngerprint checking as compared to the other methods.


R(n) =n 1+R( B l), if n > t L J B For a generic hidden volume construction, the number of block plog22nl n operations using Path ORAM is then max·A( max ).

for this construction the total number of access is justSimilarly, we can de.ne relations W (n) and R(n) for our write-W (n), since we do not divide the system into separate volumes.


Due to the theoretical limitation, to improve the accuracy of a regex-based approach is extremely hard.

the existing vulnerability signature approaches with sequential matching cause low throughput.


2.1 Application Scenarios We fully respect that people have the right to protect their privacy, so the most important goal of this paper is not to propose new tracking techniques to invade people s privacy, but instead to bring a new possible privacy attack into people s attention and raise an alarm of such new user tracking method.

as a device .ngerprinting technology, the proposed user tracking method itself is neutral, so if it is used properly, it could bene.t our society to a large extent.


In this paper, we focus on TCP .ows, becauseTCP carriesabout 90% of Internettraf.c[16],andpopular anonymity networks (e.g., Tor [17]) currently only support TCP-basedapplications.

the same idea could be appliedtoother end-to-endprotocols.


In one of the most recent attempts, Au and Croll proposed a privacy-preserving centralized e-health system to provide access to health record data from medical databases distributed across various clinics and hospitals [1].

in the related .eld of voting, Je.erson et al.


Hence, the adversary can no longer enforce a jump from one library function to another one.

he is still able to jump to an arbitrary instruction within the current function.


Cryptography couldbe usedin step 5toprevent anattackerfrom modifying the ActivatedRoles in transit.

in some applications, RoM and RsM may exist on the same physical machine, so encryption may be unnecessary.


UCS inherits same principle and structure of XCS where an initial population of rules is derived from training data.

it di.ers from XCS as (1) it is based on a supervised learning scheme that computes .tness instead of reinforcement, (2) the GA is applied to correct the rule-set for updating its population, and (3) it does not use a prediction array.


So, the correlation coefficient value of this point is low because of the differences between two traces, correct trace and faulty trace.

the squaring operation of loop normally achieves a high correlation coefficient.


Contest [9] seeks to prune redundant event sequences by checking subsumption conditions, and can reduce the running time of symbolic execution to 5%-36% of the original execution time.

the event space is still large after the pruning and the path explosion problem still exists.


Vulnerable embedded devices clearly exist in large numbers in the wild.

it is often believed that embedded operating systems are too diverse; and capturing the long tail of this diversity is required to carry out large scale exploitation.


Its security can also be reduced to the collision-resistance of the hash function.

the Vau05 protocol requires the use of a secure OOB channel, and the human work to send/compare a 160-bit LAS is quite heavy.


In the current framework, DSMS server is assumed to be secure, trustable and independent to both stream providers and stream users.

in ERP 2, the government plays both server and user roles.


Namely, such a result increases the .exibility of security analysis.

if we know that some similar notions are actually not the same, then we should try our best to construct cryptosystems which are secure w.r.t.


The AC policy Bill wishes to enforce for users requiring access to his data is the following: BILL policy: Any user with an e-mail name in the .edu or in the .gov namespaces is authorized to read any information.


For those computing units thatexecute tamperedveri.cation codes, the minimum time for .nishing their tasks alone can be estimated in the same way as estimated on uniprocessor platforms [16, 15].

the estimated time cannot be used as the timing thresholds if the adversary is able to accelerate the remaining computation process by using the idle computing units that .nish the execution of the legitimate veri.cation code.


INTRODUCTION Due to the rapid evolution of data collection and storage technologies, extracting knowledge and hidden patterns from stored data has become a major necessity for individuals, companies, and government agencies.

applying data mining techniques to extract information is considered a challenge when the data is distributed over multiple owners, and each data owner is concerned about the privacy of individuals in his data.


During all processes executed by the holder, appropriate privacy techniques are required to protect people s privacy.

the holder may disseminate the personal information to .rst responders.


4.1 Security schemes in a node The SAHNet connection protocol ensures a secure communication environment.

it may be slightly cumbersome to use, since for each connection, the user has to undergo a series of steps, out of which none are present in the current networking environments.


These approaches require special hardware components to provide secure storage and randomness for TEE.

these hardware components are not always available in devices.


As mentioned above, they might route or forward data in multi-hop situations, but there is no need for an applied end-to-end communication.

to ensure authenticity and data-origin-proof, it will also be necessary for, e.g., the sink to verify that certain received aggregated data has been aggregated in a correct way, set aside the meaning of correct.


After execution of the protocol for oblivious NFA evaluation, AH 1More precisely, disclosure of < reveals the size of the accept state sets |<|.

by adding a special state that aggregates occurrence of acceptance, any NFA can be modi.ed so that |<| = 1 always holds.


as all double-spent transactions were received by at least one observer within few seconds.

given that Adelays the transmission of TRA, our results show that only a subset of the observers receive TRA.


As with these host-based systems, if an attacker has already achieved code execution privileges, it may be possible to evade or disable the host agent.

by reducing the complexity of the host agent by moving detection into the network, it is possible to reduce the vulnerability footprint of host software that may lead to elevated privileges or code execution.


Variance of PSNR is a metric to evaluate the smoothness.

it is not appropriate in evaluating the rate adaptation algorithm; because the average variation of PSNR reflects mainly the effect of the time varying bandwidth instead that of the rate control algorithm.


Since Appel and Felten proposed PCA, many systems have adopted the proof-carrying approach (e.g., [6, 23]).

these typically use only one authorization logic for the entire system and do not consider interoperation between two or more di.erent authorization logics.


While there was a "Trusted Network Interpretation", the interpretation was in some senses a permutation of the central assumptions of the Orange Book.

the Common Criteria allows one the freedom to specify a secure kangaroo if one wishes, provided one uses the proper terminology, and can adequately state the threats, goals, mechanisms, procedures and countermeasures which apply to the kangaroo security domain.


Business process should adopt effective access control policies to overall resources involved to prevent unauthorized access.

there is a deep expectation from end users that all their personal information should be protected, rather than be unrestricted exposed.


This shows that our taint tracking additions to QEMU incur an approximately 2.2x slowdown when we are in the emulator.

the goal is to avoid entering the emulator as much as possible.


This is currently possible, since each service provider will give a di.erent tuple to the user.

this approach still requires that users execute the enrollment procedure at least once with each di.erent service provider.


In a textual password setting, many users might input their confirmation within half minute.

since it usually takes much more time to either create or memorise a DAS password than a textual one, and since people were not so familiar with graphical passwords, we have assumed that on average the users repeat the password for confirmation after a longer period.


modify the Wu-Manber algorithm in order to run string matching on GPU [23].

it is reported that the Aho-Corasick algorithm outperforms the Wu-Manber algorithm in terms of worst-case performance [33].


Human physiological and/or behavioral characteristic can be used as a biometric trait when it satis.es the requirements like Universality, Distinctiveness, Permanence and Collectability.

in a practical biometric system, one needs to consider some other issues too like Performance, Acceptability and Circumvention [2].


When a node is added, its information is added to the coordinator s table.

this method requires that each node be successfully authenticated.


[5] for security-investment is based on factors such as trustworthiness of users.

they do not address the problem of eliciting the necessary information for the risk calculations.


Format alteration is the simplest and least e.ective method among others.

even this simple method sometimes lets malwares avoid detection tools.


[1] proposed distillation codes as a means to thwart pollution attacks against SAIDA.

distillation codes require significant communication and computation overhead.


Several consent models with associated consent templates have been identi.ed [7, 23], and a few e-Consent based systems have been built upon these guidelines [22, 19].

it is still essential to develop a systematic approach to determining how a patient s consent is expressed and at what granularity the consent is applied to the EHRs.


Furthermore, from a purely mathematical point of view integrity is the dual of con.dentiality so the results from one should carry over to the other, and intrusion detection can entail con.dentiality concerns, in addition to integrity or availability.

the differences between con.dentiality and integrity go well beyond the mathematical, as illustrated by the differences between Biba s model for integrity [3] and those of Lipner [33] or Clark andWilson [9].


ample, if an attacker compromises a phonebook of a device -we can t obviously give the CEO s call list.

an administrator could choose some less sensitive numbers that would be representative of numbers that would belong in the phonebook of the CEO.


For instance, a malicious third-party component provider can invoke typical security-sensitive operations such as the retrieval of cookies, navigation of the browser to another page, launch of external requests or access and updates to the Document Object Model (DOM).

with the emerging HTML5 speci.cation and APIs, the impact of injecting and executing arbitrary Java-Script has massively increased.


An attacker is highly unlikely to be familiar with the friends of a victim at least under the threat model assumed by Facebook and there lies the security of recognizing one s friends as a security mechanism.

by acquiring accurate facial models of a victim s friends we are in possession of the key to solving SA challenges.


Similarly, the ability for an attacker to derive a private key through brute force methods can be hampered by using large key sizes.

there are areas of cryptographic weaknesses that these systems have much less control over.


On a general note, some of the exposed chord diagrams exhibit a less than optimal readability (for example, Figure 5).

they are di.cult to improve due to the fact that they intend to display a great and hardly reducible amount of information.


Traditional security considerations revolve around protecting the network connection s confidentiality and integrity, protecting the system from break-in, and protecting the user s private information from unintended disclosure.

one area that has long been neglected is that of service availability in the presence of Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page.


We note that their work considers a model where a party can be adversarial together with the (rate-limited) adversarial channel.

our impossibility result works in a model where parties are semi-honest, and only the channel can be adversarial (and rate-limited).


In the case of changing order of concurrent operations, the authenticator Tj@R is still valid (it passes the check of Algorithm 3 -line 7).

if R continues to work on the document and adds new operation opk after opj, then commits an authenticator Tk@R, other sites cannot change the order of opi, opj and opk since this misbehavior will make the authenticator Tk@R invalid by the checking procedure in Algorithm 3 -line 8.


For example, in Figure 3, all the r 2 values below 0.01 are dropped.

we can still .gure out haplotype frequencies for individual haplotype blocks using the r 2 within blocks, and connect different blocks together by running a maximum likelihood estimator over the remaining LDs between blocks.


The interesting point here is that corrupted data is actually an information loss, and once this happens, it's difficult for a user to retrieve his sensitive information.

it is also true that the type of data that gets corrupted on the cloud, defines whether it can be considered a privacy concern or not.


This implies that q should be at least 64 bit long for typical cryptosystems such as RC5.

processors in sensor nodes usually have much smaller word size.


it provides some more privacy since it is not immediately clear when the exception occurred.


The discussion so far has mainly focused on negative feedback.

sDT can be used for positive feedback as well.


In contrast, for the compression algorithm BZip2 only a few more page faults are generated for the relatively steady code access.

the additional checks on every access result in a slightly broader distribution of page fault times.


For instance, Andrubis employs Taint-Droid.

it may take signi.cant effort to extend TaintDroid to support all SDK target versions and to work with a range of physical devices, as A5 does right now.


Critics would argue that any government intervention in the media marketplace in an attempt to protect privacy is an unwarranted intrusion on the freedom of press.

if the government cannot be trusted to regulate the press, why should anyone believe that the press will do a better job of showing self-restraint and exercising higher moral and ethical judgement, especially in light of increasing market competition?


Note that role mapping problem and activation checking problem seem to be straight-forward in simple RBAC systems.

in presence of an RBAC policy with hybrid hierarchy and SoD/cardinality constraints, this problem can be very complex [7].


Then, Fong [12] recently formulated this paradigm called a Relationship-Based Access Control (ReBAC) that bases authorization decisions on the relationships between the resource owner and the resource accessor in an OSN.

none of these work could accommodate privacy control requirements with respect to the collaborative data sharing in OSNs.


Given a policy P , we can remove one by one all the authorizations that satisfy the redundancy condition without changing the behaviour of the policy.

by removing authorizations from P we may change the redundancy condition for other authorizations.


We can conclude this sectionby observing that, combining basic methodswith boolean operationscanbehelpfulto selectadifferent combinationofFARandIPR.Thatis,asitis possiblebyvarying T and ß ,also with boolean combinations we might look foradifferent value of one of the performance metrics (FAR and IPR).

we observe that also with boolean combinations is not possible to improve bothFAR and IPR at the same time.


AGILE SECURITY ANALYTICS In order to meet the demands of their business leaders, security departments need ways to better understand organizational data to ensure the trustworthiness of their spaces.

these capabilities are by and large beyond what s found in today s security intelligence products.


We compute the CPU execution cycles of CPUID instruction to measure the overhead of processor intercepting in Windows XP.

we use McVoy s lmbench program [8] of version 3.0, as this addresses many testing issues, to examine the overhead of VASP protecting Linux system.


Users demand strong security and privacy guarantees.

security and privacy protection alone cannot ensure that users will embrace PS applications.


This may seem like a lot of overhead even for a singlebit wide SECTAG.

a D-L1 cache is usually much smaller than a uni.ed L2 cache.


Hence, there is only one kernel running: no security isolation exists between split-base and split-hardened kernel code, and if the kernel is compromised in either of these execution contexts, it is compromised in both.

compromising it while running in split-hardened mode is more dif.cult than in split-base mode.


Whereas after analyzing the statistical data, the participants in Group2 have not shown too much advantages in the aspect of click-numbers though they actually generated their passwords more securely.

we .nd that the user guidelines are very e.ective for new users who did not use the graphical passwords before in terms of the participants feedback as well as the password-pattern analysis.


If the IdP URL is allocated dynamically when the connection begins, the URL should be sent to the IdP through the connection and displayed on the mobile phone terminal LCD.

dynamic URL allocation reduces the risk that an attacker accesses a user sIdP.there isthe demerit that a user cannot remember the URL of his/her IdP.


Notice that for medium to high DWRs the differences between the two capacities are negligible, meaning that the steganographic constraint has nearly no impact on the achievable rate.

when the DWR is reduced, the capacity of the steganographic system is upperbounded by the maximum capacity given above, i.e.


TPM-based attestation protocols use measurements, typically hashes of software packages loaded for execution, to establish the trustworthiness of a platform.

this approach may reveal speci.cs of the cloud provider s software infrastructureto competitors.Forexample, measurementsmayrevealthe use of a module implementing a particular scheduling algorithm or a performance-enhancing library.


Bypassing these client controls by overriding the shell extension or breaking the clipboard viewer chain may cause the client to lose its functionality, but does not help to obtain any confidential information because the DOFS filter driver filters the file content on the server side.

other client component such as the screen capture controller requires stronger protection to ensure the integrity of the DOFS architecture.


5.2 Password Manager Since Versipass does not store passwords, there is no risk that an attacker who gains access to Versipass might be able to access the user s accounts.

such an attacker would be able to access personal information (the list of sites where the user has accounts, and the user s usernames), and cause signi.cant disruption for the user (by changing their category passwords or by deleting information).


If the compromised node cannot modify the received aggregate, i.e., it can only forge a false reading of its own, then the aggregation data may range from 98.7F(100*50+32 ) ~ 51 101F( 100*50+150 51 ), which does not deviate far away from the true average value.

if it can launch a count changing attack by reporting a bogus large count value, then it can make the average result be any value in the range from 100F to 150F (assuming its own reported temperature is 150F).


The use of a Bloom .lter has been proposed as a space-e.cient probabilistic data structure for the carriage of fragment hash values [24].

albeit the paper considers the presence of an active adversary, the chosen error probability of the Bloom .lter does not re.ect this.


The TMI reference monitor is invoked implicitly upon access to security-relevant resources, as described above.

there are cases when code within an STM transaction must explicitly query the security policy.


Thus, for reducing the risk of database overwhelming we diminish the time interval by applying a coefficient.

ß implies how fast these amounts of alerts have been generated.


This means, of course, that the number of user-and permission-role assignments will increase (because such assignments are often implicitly generated by assignments to other roles in the presence of a role hierarchy).

it does mean that .at RBAC+ is su.cient for specifying all spatio-temporal ST constraints.


The main idea is to off-load some of thepatient s(server s) computationtothecloud.

weimmediately acknowledge that involving the cloud triggers the risks discussed at the end ofSection 3.1.


To improve performance, we use Xen with asynchronous I/O support.

doing so introduces its own set of challenges when trying to associate blocks with the process that made the request.


In such systems, the processes attempt to deceive the interacting user by crafting an arti.cial response.

if the user knows the deceptive behavior, e.g.


As previewed in Figure 1, while the information disclosed in the public pro.les covers many classes (e.g., demographics, location, education, and af.liation), it is generally coarse-grained (and thus less identi.able and less sensitive) and static (and thus less timely).

the information leaked on to the network is .ner-grained and/or dynamic which closely re.ects users cyber and real-world activities and interests.


As shown, previous studies on PCCP and PassPoints have used 5-click passwords with a theoretical space of 243 .

evidence suggests that many users today choose passwords with much lower entropy, e.g., the Weir et al.


The security strength of the Diffie-Hellman key exchange protocol comes from the difficulty of the discrete logarithm problem [2, 11].

an attacker can relatively easily sniff and capture the public values used for the key exchange, R1 = gx mod p, and R2 = gy mod p. given R1 and R2, it is computationally difficult to find x and y.


The overall reachability analysis will then show that there is a direct information .ow path through the encryption device, connecting the high-security domain to the low-security domain, via pins a, b, c, d, e and f in all of the EncOff modes.

this is not a security concern it merely tells us that data .ows freely through the device when it is not required to encrypt, as expected.


The feature vector has the following property: if two malware programs are similar to each other, so are their feature vectors.

if two malware are dissimilar, their feature vectors may or may not be similar.


the results of this work are not applicable to the fuzzy vault.


Here the authors obtain a certi.cate on their work which they can use as an o.cial proof.

authorship and licensing proofs are much more complicated than this.


NativeGuard: Protecting Android Applications from Third-Party Native Libraries Mengtao Sun Gang Tan Lehigh University Lehigh University 27 Memorial Drive West 27 Memorial Drive West Bethlehem, PA 18015, United States Bethlehem, PA 18015, United States  mengtao.sun@lehigh.edu gtan@cse.lehigh.edu ABSTRACT Android applications often include third-party libraries written in native code.

current native components are not well managed by Android s security architecture.


This is because adore 2.6 modi.es the function pointers in both kernel global and kernel heap.

mA K E UP cannot identify the kernel heap pointers statically.


Social engineering is the most powerful tool for an attacker to access this knowledge.

people freely publish information in online communication and collaboration tools, such as cloud services and on social networks with very little thought of security and privacy.


It would seem that at least the approaches targeting at arbitrary, interacting bad measurements (e.g., [4,12,21,25]) can also defeat the malicious ones injected by attackers, since such malicious measurements are indeed arbitrary, interacting bad measurements.

despite the variations in these approaches, all of them use the same method (i.e., lz - H xl >t ) to detect the existence of bad measurements.


The model allows application updates to be recognized as authorized by a party with access to the original signing key.

changing keys or certi.cates requires that end users manually uninstall/reinstall apps, losing all non-backed up user data.


Such MAC VM systems promise comprehensive control of system information .ows.

due to functional requirements (e.g., Xen uses Linux kernel services and drivers to bootstrap function), these emerging systems are unlikely to have a highlevel of formal assurance [5].


Some of these approaches are based in the realms of information retrieval and data mining such as [2-5] and have yielded some promising results with respect to identifying whether a program is malicious.

many of these research efforts are faced with the curse of dimensionality [2], which refers to the challenges of computing in a high-dimensional space.


The second patent, by Sheymov [4], describes a technique to hide the more generic "cyber coordinate" to help guard against network intrusions.

this technique requires creating a permanent identi.er, therefore clashing with the goal of privacy in MT6D.


attack on Grain-v1, by using a guess-and-determine attack to decrease the sampling resistance by R =2-18 which results in lower pre-computation complexity.

the 20 Table 1: Comparison of TMD Attacks on Estream Table 2: Comparison of TMD Attacks on Block Ci-Finalists phers Cipher Key IV State Size Our Attack Existing Attacks HC-128 Rabbit Salsa20 SOSEMANUK Grain-v1 MICKEY-v2 TRIVIUM 128 128 128 128 80 80 80 128 64 64 64 64 64 80 32778 513 512 384 160 200 288 No Yes Yes Yes Yes Yes No No No No No No No No Note : The existing attacks refers to BS-TMD, HS-TMD and DK-TMD attack.


The kernel has been modi.ed to include the OpenVZ patches as described in the following Section 3.4.

any other Linux-based instant-on OS with a 2.6.18 kernel could be used.


Readings or messages from several sensors are processed at a data fusion node and aggregated into a more compact report before being relayed to the parent node in the data fusion hierarchy [13].Passive participation is another form of in-network processing in which a sensor node can take certain actions based on overheard messages [14, 20], e.g., a sensor can decide to not report an event if it overhears a neighboring node reporting the same event.

particular keying mechanisms may preclude or reduce the e.ectiveness of in-network processing.To support passive participation, it is essential that intermediate nodes be able to decrypt or authenticate a secure message exchanged between two other sensor nodes.Thus, passive participation of secure messages is only possible if multiple nodes share the keys used for encryption and authentication.if a pairwise shared key is used for encrypting or authenticating a message, it e.ectively precludes passive participation in the sensor network.


This type of access control is referred to as static authentication.

we .nd Continuous Authentication (also called Active Authentication1), where the genuineness of a user is continuously ver 1http://www.darpa.mil/Our_Work/I2O/Programs/ Active_Authentication.aspx Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for pro.t or commercial advantage and that copies bear this notice and the full citation on the .rst page.


Course Description: Students spend the first 7 weeks of the class learning through more traditional methods, i.e., lecture and reading.

for the next 7 weeks of the class, students are assigned to a team tasked with performing an information security risk assessment for a client, which will be a K12 school corporation in the west central area of Indiana.


This is necessary since examples of benign PDF documents with JavaScript content are quite rare, and it takes a lot of manual e.ort to verify that they are benign.

examples of malicious PDF documents abound on malware collection systems, and their maliciousness can be ascertained with high con.dence if they are detected by antivirus systems.


They do not provide a general approach to protect against all attacks in the wild (see Section 7 for more discussions).

a desired property is that the user relies on a self-contained solution that protects against any threat of identity theft be it a phishing or be it malware attack.


As a bene.t, this can be used to reduce the search space required for graph/subgraph isomorphism.

this approach may not .nd the least expensive sequence of edit operations, and may even fail to .nd a transformation from one attack strategy graph to (the subgraph of) another.


Every time the system processes the queue with the %eip values, there is potentially more information available that can be used to obtain a more complete picture of the program s CFG.

we expect that there are diminishing returns.


These results suggest that humans can tolerate small character rotations with minimal impact on performance.

a larger rotation can have a much more dramatic impact on human accuracy.


1.1 Prior work The idea of quantum money was introduced by Wiesner in 1969, when he proposed using the no cloning theorem to generate bills which can not be copied [1, 2].

in Wiesner s original de.nition the only entity that could verify the quantum money state was the mint that produced it.


Overcrowded hotspots are a necessary consequence of the lack of coordination among telecommunications operators, who only grant access to their customers and seldom have roaming agreements.

this model prevents small operators and institutions from installing publicly accessible hotspots.


There are many vulnerabilities such malwares in existing mHealth systems [3] [4].

a patient s health information may contain sensitive information such as identity data (ID), sexual health (SH), mental health (MH), dermatology health (DH), addictions to drug or alcohol, abortions, etc.


A lot of graphical password schemes have been proposed to enhance computer and network authentication.

there is seldom work to investigate the e.ect of giving user guidelines to users on creating their graphical passwords.


On the one hand, any role-dependent IA-DHKE, like robust (H)MQV and KEA/OPACITY, does not satisfy, by de.nition, the completeness property of role-independent SKsecurity.

any role-independent IA-DHKE like the basic (H)MQV is totally broken according to roledependent SK-security (as the session-key of the test-session can exist in a non-matching session by the cross-message attack [25]), which might be viewed as more dangerous.


Many watermarking schemes have been developed for gray-scale and color images.

these watermarking schemes cannot be applied to binary document images, since such schemes achieve embedding by small changes to the gray/color pixel values which is not possible for binary values, and also since perceptible image distortion of binary images (see section 2.3) is quite different from that of gray/color images.


To the best of our knowledge, MoCFI is the only thorough CFI enforcement solution for iOS, which is one of the two most widely used smartphone operating systems on the market.

their approach cannot easily be used in practice.


Clearly, it is easier to justify to corporate management that spending resources to protect against high impact attacks is a good investment.

concentrating on only the high impact threats is not wise, as even small threats can be significant if the attacker is persistent, affecting the business or another entity in the supply chain.


For elderly people, conceiving technologies for increasing their autonomy, so as to enable them to self-manage their life is of utmost importance.

when it comes to smart home, once all appliances in a home are automated and connected through internet, it becomes essential to consider issues of security, especially security configuration.


At the .rst glance, the top q-grams indicate only little malicious activity.

they reveal the presence of a XOR-based decryption routine.


For maximal row tableaux, a subclass of tableaux queries, query containment is intractable.

since the query containments we check are of a special form, we show that perfect privacy in this scenario can be enforced with a very simple algorithm.


The feed-forward steps may be seen as providing possible control in the message expansion region which can in fact be used to correct perturbations in the higher rounds.

we could not actually see how this could be done.


The event s participants appear in the Facebook event with the identity of the account they provided.

textual posts, comments, likes and photos are posted in the Facebook event in cleartext, to maintain the .exibility and convenience of the Facebook interface.4 video and audio recording posted to the event are uploaded using the Dropbox conduit (encrypted with the shared event key), and a URL to that content is posted in the Facebook event.


The mostdirect is to attempt to use a secret that has been sent in the contents of the OTR conversation itself.

the online instructions that accompany OTR speci.cally warn against sending the secret over theInternet, whether over IM or email.


CRAFT: A New Secure Congestion Control Architecture Dongho Kim , Jerry T. Chiang , Yih-Chun Hu , Adrian Perrig , and P. R. Kumar Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, IL, USA Department of Electrical and Computer Engineering, Carnegie Mellon University, PA, USA {dkim99,chiang2,yihchun,prkumar}@illinois.edu, perrig@cmu.edu ABSTRACT Congestion control algorithms seek to optimally utilize network resources by allocating a certain rate for each user.

malicious clients can disregard the congestion control algorithms implemented at the clients and induce congestion at bottleneck links.


Similarly to us, they employ periodic quantization.

because of the constant periods, the reduction of the timing channel bandwidth is only linear.


It means that spam campaigns are divided into small pieces of clusters for a large value whereas they contains mixture of spam campaigns for a small value.

we con.rm a rapid change Figure 5: Number of spams, time period and number of IPs for top 100 campaigns of the amount of clusters around 85 of match degree.


Once highly motivated bot developers know the HOP approach, it is possible for them to create more advanced game bots to evade the HOP system.

the purpose of the HOP system is to raise the bar against game exploits andforce adeterminedbotdeveloper to spend signi.canttime and e.ortinbuilding next-generationgame bots for detection evasion.


This information is used to guide future trust-based decisions about interaction.

while trust management is a component in security decision-making, many existing reputation-based trust-management systems provide no formal security-guarantees.


This means that the packing of inputs will a.ect LSBs complexity in a slightly negative way; given the additive constants ax in the previous equations and a .xed s, the difference in complexity between running h LSBs and running one LSBs with h packed integerswillbe(h-1)ax (independent of the bit-size l of the integers), while the number of rounds will increase in 2l(h-1), as without packing the h gates can be parallelized.

the computation complexity is O(s 4), so using Damg°ard-Jurik encryptions would suppose a considerable increase in complexity, what justi.es the preference for packing only using s = 1.


They demonstrated their technique on three example programs (about 30 lines each), as well as real applications such as Apache, showing that about 90% of the time, control could be successfully returned to the attack code.

the focus of their evaluation was to demonstrate the ability of their symbolic execution technique to generate con.gurations that can return control back to the attack code.


it appears to have no purpose other than to collect sensitive information from credit union members.


The notion of a virtual black box that approaches perfectly secure hardware protection which shields all internal analysis of a circuit structure remains impossible to produce.

there remains the question of whether any form of variation provides any useful form of protection.


In Figure 4(a), the total number of ETAs in the DG is 14.

after merging as in Figure 4(b), the number of ETAs is reduced to 5.the merging sacri.ces security.


SASSY Fundamentally, a language-independent solution could require that people speak the hexadecimal digits of the hash of the key, e.g., a PGP .ngerprint or a Global Unique Identi.er (GUID).

people are not well suited to speaking long strings of digits.


In principle, PSI could be deployed on a system-wide basis, and use a shared cache across all users.

currently we rely on a simpler scheme that uses a per-user cache.


As the number of releases increases, the constraints imposed on the next release Rn become increasingly restrictive.

this does not necessarily require more distortion because the new records Dn may help reduce the need of distortion.


First, during registration, users typically have to disclose extensive amounts of personal information, which is often of no direct relevance for the service at hand.

the accumulated sets of data pose the imminent danger of accidental leakage or theft, which may result in consequences such as .nancial loss or damaged reputation of a service provider.


If Revent-past and Rnormal-past are of equal cardinality, then Revent-past is a better predictor of the report Revent-present at pre.x length n if: |Cn(Revent-past) n Cn(Revent-present)| > |Cn(Rnormal-past) n Cn(Revent-present)| (4) If temporal uncleanliness exists, then we expect that unclean reports will consistently be better predictors of future unclean reports than a control report.

we note that due to spatial uncleanliness, an unclean report will populate fewer equally sized blocks than an equivalent control report.


This can be useful in scenarios where multiple actors process and potentially transform a document throughout a business process.

this same property can be exploited by an adversary allowing the undetected modification of documents.


Although application programmers are freed from taking care of the secure secrets handling, it is di.cult to change the encryption algorithms according to application requests.

we allow application developers to program cryptographic algorithms protecting the secrets to be transferred from the isolated LS to the main memory.


The problem of untrusted device drivers has currently not been addressed by our TVMM prototype.


Reviewing the results from both user studies, we conclude that although Line Snaking has better defence performance, the Disappearing Stroke technique is more appropriate for general deployment, since it offers reasonable protection and good usability, and it is also preferred by the users.

with regards to technique choice, it is possible that users themselves should be able to decide on which defence technique to apply depending on their situation, as our results indirectly show that although users reported Disappearing Stroke as more comfortable to use, they immediately spotted the security advantage of Line Snaking.


SpamBayes has a large (one could say in.nite) feature spaceofpossibletokensthatcanoccurinan email message.

while there are many features, the in.uence the adversaryhason eachisseverely limited.


Moreover, it seems that generating signatures akin to the self-certifying alerts (SCAs) in Vigilante would be all but impossible for Minos.

while Argos works with physical addresses also, we explicitly target emulation in software to provide us with full access to physical-to-virtual address mapping, registers, etc.


Next, we analyze the decryption complexity (and .nd that it is too large).

some of the analysis applies to the .nal scheme.


Trapdoor Permutations (TDPs) A family of trapdoor permutations (TDPs) is a family of permutations such that it is easy to randomly select a permutation f and some trapdoor associated with f. Furthermore, f is easy to compute and, given the trapdoor information, so is its inverse f-1 .

without the trapdoor, f is hard to invert on random inputs: No PPT adversary A, given y = f(x) for random x, can .nd x with probability greater than ETDP, which is negligible in the security parameter e of the generation algorithm.


Any and all qualifying elements bounded by a node s MBR are contained within that node or its subtree.

r-trees partition space for search optimization such that nodes may overlap or some space may not be contained within any node (Figure 2(b)).


In most cases, the switching power model could help reduce the number of variables, due to the fact that the number of switching gates is much less than the number of gates in the entire circuit.

from the perspective of HTH detection, we should consider using leakage power, because it covers all the gates in the circuit and thus makes the HTH impossible to hide from our measurement.


In the upload user selection phase, each user calculates the value of w for which the NE can be achieved, and then decides whether to upload or not based on w. Recall that the desired NE is achieved if and only if we choose an appropriate value of w. If the players are aware of the upload costs of their opponents, i.e., c1 = c2 = · · · = cn, it is easy to get w = ck .

since each player loga(1+;(k+1))/(1+;k)  does not know the privacy levels and privacy costs of others, we need to estimate the value of ck.


The de.nition of this interpreter is completely straightforward; we omit it for brevity.

in §6 we compile this rule table into the IFC fault handler for the concrete machine.


Finally, the master state machine reads CD , moves from state 6 to state 4, and outputs ß .

the slave state machine reads 0ß , and moves from state 5 to state 2 which represents the final state of the pattern .*AB.


In fact, the privileged VM is often a large piece of software, therefore, it is more prone to contain vulnerabilities that can be exploited by an attacker.

unrestricted access to the privileged VM  does not give full privileges over the physical machine [10].


The characteristic of the Kaspersky antivirus software, for example, is having a strong ability to search and kill unknown viruses, but it often kills some normal files by mistake in the process of using.

the greatest feature of the 360 antivirus software is free, but its ability to search and kill viruses is general.


Both, for applications and games, the chance of manually .nding a working crack or keygen is roughly one third (33%).

for all applications we tested, only 13.95% worked and were free from malware.


APK information should be unique to individual APKs; thus, organizations can share the same values, and it is ine.cient if individual organizations collect the APK information in isolation.

the results from risk evaluations should di.er depending on how APK information is evaluated; individual organizations could work on producing their own evaluation results by using their own know-how and expertise, or individual organizations could choose evaluation results produced by third-party organizations they trust.


This work is largely orthogonal to declassi.cation policies, which, in the context of this paper, are concerned only with possibilistic security assurances.

the conditions for declassi.cations could perhaps be useful in specifying or bounding channel capacities.


The mechanism assumes that the canary word is overwritten when a buffer overflow occurs and overwrites the return address.

it is possible to change return address without altering the canary value [3].


Cj is being introduced during the credential exchange phase.

s is obtained by the terms derived from the tree, and it follows from case (i) that this is not pos ' sible.


It is a key step in the IC applications regarding cryptography, security, and digital rights management.

gLC is challenging due to the existence of manufacturing variability (MV) and the strong correlations among some gates in the circuit.


In any case, the fear of detection by FRAppE will increase the onus on hackers while creating and maintaining malicious applications.

we argue that several features used by FRAppE, such as the reputation of redirect URIs, the number of required permissions, and the use of different client IDs in app installation URLs, are robust to the evolution of hackers.


In this case, access of client-side scripts to these cookies is blocked by the browser.

other attack techniques such as cross-site tracing [30] and using XMLHttpRequests [37] can be employed, allowing an adversary to steal HTTP-Only cookies.


For example, when Apple migrated from PPC to x86, they may have wanted to produce a single program bpip that behaved the same as separately compiled programs bx86 and bppc.

one may also want the PIP s behavior to be di.erent for each platform, e.g., a mal 19090289016 decodes to nop; nop; .byte 0x28 ; nop on x86, which is not a valid instruction sequence.


We also check if these malware are packed or not using PeID and report the labels in Table 2.

some of the malware that PeID did not detect could also be packed.


Compared with the results above, the multithreaded version pl pl = pl = leaks less than the sequential version because the non-determinism Lp = H(h) - µ(T001)H(h|T001) - u(T= pl in the scheduler introduced in some random noise.

if = 010) 111 )+ 1 4 × H( 111 4 × 0) the attacker can track the program (by observing the scheduler se 1 010)H(h|T=2 - ( 4 × 0+ × H( )+ , , 42222 =1.5 bit; quence), the leakage becomes larger.


DNS-based Authentication of Named Entities (DANE) securely binds certi.cates with domain names using Domain Name System Security Extensions (DNSSEC), enabling domain holders to assert certi.cates without reference to CAs [8].

the security of DANE heavily relies on the security of DNS operators.


Heuristic-based malware detection identi.es malicious code by statistically analyzing its structure and behavior without depending on prior knowledge of the malware.

this approach su.ers from false positives as well as false negatives as decisions are based on statistical models for maliciousness.


If the device appears to be in use (i.e., the accelerometer sensor is activated), and its recent location traces are inconsistent with the PoS location, then the transaction may be rejected or require further corroboration, depending on policy.

if everything is consistent with the legitimate user making the purchase, the clearing house may signal to the PoS that no signature is needed resulting in a fasttrack checkout.


Consequently, the same instru- 5MIP s basic idea of using variable-sized chunks to restrict indirect branches clearly applies to C++ code.

a code-sandboxing framework needs a system-call interposition mechanism to prevent/restrict dangerous system calls such as mprotect.


Therefore, the order of unique infected sources detected by the telescope will be close to the actual worm infection sequence.

when Tin approaches or becomes lower than Td, it is likely that more hosts will be infected within Td, and these hosts may be detected out of order, thereby causing lower correspondence between the infection sequence observed at the telescope and the actual worm evolution.


The sensors capture and analyse the contents of packets passing through the choke point.

network-based IDSs/IPSs cannot analyse encrypted packets, and the volume of traffic may overwhelm them.


If the first component contained a required measurement probe then it is necessity to obtain required information with some other means, or alternatively, change also the utilized indicator lest the original measurement probe is not needed anymore.

this requires that unavailability of measurement probe is recognized.


The resulting virus variation still exhibits the same malicious behavior.

any detection mechanism based on consecutive and ordered sequences such as N-Gram could be fooled.


Actually, typical data-centers usually have strict control of physical accesses as well as surveillance cameras to monitor and log such accesses.

as the disk storage might be easily accessible by operators through the VM management stack or evenphysical maintenance(such asdisk replacements), we assume thatthe externaldisk storageis nottrustworthy.


As a result, it is not able to detect elusive malware that may be hiding entirely in the memory (e.g., kernel-level rootkits).

vMwatcher examines both volatile and persistent states for malware detection.


Thus, it will only introduce little runtime overhead to the servers to log them directly using emulated keyboard of virtual machine.

this is not the case for network packets.


CONCLUSIONS Dynamic taint tracking is an e.ective approach for detecting privacy leakage on mobile devices.

designing a good taint tracking system requires .nding the proper tradeo.


A simple scoring function could therefore count the number of distinct network endpoints (IP addresses and DNS names) contacted by the analyzed samples.

not all network traf.c observed is related to C&C, or to malware s auto-update functionality (which can be seen as a type of C&C where commands are delivered in the form of executable code).


We could also record the results of these instructions as ..

for programs that heavily perform these operations, the performance for both record and replay may greatly degrade.


Another possibility is to insert instructions to implement the intended protection operations directly instead of recording them in a separate action table.

the action would require several instructions to implement, which indicates more changes to the standard ISA of the processor and more code space overhead.


The use of simple machine learning techniques to modify the parameters domains is an e.ective mechanism.

this modi.cation removes a value from a parameter s domain.


All our constructions of multiset batch codes go through primitive batch codes.

we show that this is not without loss of generality, because for primitive codes, a stronger bound holds.


We also found that many major vendors use similar limited number of meters per collector due to limited bandwidth or coverage, in power line communication and WiFi, respectively [1, 7].

vendors might support di.erent models of the AMI technologies that o.er di.erent capacity of handling meters.


When the population of V. .scheri is low, the autoinducer has no e.ect.

as the population of V. .scheri grows, the concentration of 3-oxo-C6-HSL increases as well, eventually triggering transcription of the bacterial luminescence gene, thereby producing enzymes that cause the squid s light organ to glow.


Yet, there is a reference implementation [2, Appendix A] which is still lacking the integration in an existing identity management system.

in [2, Chapter 5] or [11], respectively, the complexity of all necessary FCA operations is determined.


For some optimization aspects we combined such con- In Table 1 we see that shifting the overall decision to the 2nd or 3rd time improves the FRR, thus improving the usability of the system.

the external and internal FAR is increasing and in such manner reducing the security of the system.


The resulting P2P architecture will have high scalability while maintaining the security of C/S.

this raises issues of referee trust, selection, load balancing, and synchronization.


Since the SAML attributes provided by Science Gateways were included in a non-critical certificate extension, Resource Providers with unmodified software simply ignored the attributes.

new Science Gateway enabled software capability kits were made available to Resource Providers to use these attributes.


Instructure was the only SaaS-CP vulnerable against XSLT.

it shows how complex the different modules are.


Since each role has a high number of assigned users, it is likely that the number of involved organization units is high, thus increasing the value of the ou spread function.

if we want to reduce the average number of roles per user, we will need more ad-personam roles, then |ROLES| will likely increases.


s. if the transition function exhibits bounded nondeterminism, i.e., the range of d is always a .nite set, then such an in.nite transition sequence does exist by K¨onig s lemma.


7.7 Integer comparison protocol We now compare the protocol in Section 3 to zero-knowledge range proofs (ZK:RP) [18, 21, 22, 28], which, like the protocol in Sec tion 3, provide privacy-preserving integer comparisons.

a ZK:RP provides stronger properties than V E X (it can answer queries about ranges versus inequalities), but here our focus is on costs: the size of commitment, the length of proofs, and the number of rounds of interaction.


scheme can only be applied to the group-based deployment model, and its deployment points depend on the division of rectangles.

our scheme has no restriction on the deployment points, and hence, it can be applied to various deployment models (deployment at irregular intervals, mixed deployment by helicopters and cars, etc.).


We hypothesize that users/advocates of Tor would most likely not use their default ISP name servers and instead would choose to use public DNS providers such as Google Public DNS or OpenDNS (AS36692, which has a share of 2.06%).

more surprising is to see that many .onion queries originated from AS15169 given that Google Public DNS has an intensive caching policy in use to avoid multiple queries to the root that would potentially result in 2All of the autonomous systems listed in Table 4 have large number of IP addresses allocated to them, thus publishing them does not put the privacy of individual users at risk.


At .rst sight the plotted values seem vanishingly low due to logarithmic scale and the overall size of the feature space as denominator.

the steepness of the density s decay over increasing n-gram lengths is the crucial indicator here.


The common pre.x of the paths from root to t1 and t2 is not a pre.x of the ; path from root to te.


By diversifying code as described above, we are con.dent that a realistic ROP attack will crash at some point when it tries to call a gadget which is broken or no longer in the expected position.

by inserting booby trap hooks into the binary while diversifying, we can catch the attack and react to it directly.


(0, 1) In any PPDM problem, the accuracy of input is not very high.

nj is a very large integer and M is also very large with half length of Nj.


Also, advances in fault tolerance in particular, replication and load distribution have been very bene.cial to Web servers.

doS attacks are not thwarted by such measures since their central goal is to deny service to legitimate clients.


Currently login/password based authentication protocols are used in most of the public and private system.

using this choice for authenticating users is gradually becoming obsolete.


In information theoretic notation, the requirement can be written as I(D; S) = 0.

this is not enough because an MT technique which keeps the entirety of the attack surface static would still satisfy the requirement.


See for example Yan [20] and Spafford [21].

simple black-listing approaches generally have problems with any sophisticated dictionary based attack.


That is, they do not say in which state role r is at time t. For example, if can_activate(u, r, t) and enabled(r, t) hold, then a user u s request to activate r at time t is granted provided there are no other activation or SoD constraints prohibiting it.

if can_activate(u, r, t) holds but not enabled(r, t), then u s request to activate r at time t is denied.


In practice, we .nd the gadgets ending in the near indirect jump are su.cient to construct the JOP shellcode.

for far indirect jump, we have to make the appropriate choice of segment selector when constructing far jump code.


For example, in our experiment, it was 137 on the board and 210 on the phone.

we observed that the CBNs of di.erent devices are equal if the above properties of the devices are the same.


This gives a malicious attacker an opportunity to bypass detection.

memSherlock assumes existing hardware and software supports in modern computer systems, and does not su.er from the same false negative problem.


Cognitive passwords, also referred to as personal knowledge questions , are now often used as password-reset mechanisms.

cognitive passwords su.er from some of the same weaknesses as traditional passwords: in particular, they are often easily circumvented by targeted attacks using information gathered through acquaintances, phishing, social media and other publically available data sources [25, 67, 70].


For example, Trusted Computing (TC) technologies have been recently proposed to provide strong isolation on application platforms.

today pervasively available computing cycles and data resources have enabled various distributed applications that require collaboration among different application processes.


Clients use libdbus to talk to the D-Bus server socket.

libdbus programmers did not expect to be called from setuid binaries, so they did not .lter an environment variable that speci.es the path of the D-Bus system-wide socket.


Once the threshold for a feature is violated, the respective action will be taken to slow down or stop the possible anomaly activities.

observing the individual threshold violating events (e.g.


To support this, we have added an optional structure into the data plane to track the TCP timestamps between external and internal connections.

this is optional, because the data plane could also simply discard such options during TCP negotiation.


Integrity and Recovery: The check in REACT assures the faithful operation by the client.

if the operation fails to pass veri.cation, the server can do the puzzle itself from scratch, or give it to another client.


Again, three variants of restrictions are implemented.

pub/sub restriction functions can only limit the type within the type hierarchy, since Hermes advertisements cannot include content-based .lters.


Forty-nine of the 73 qualified people completed the actual study.

the data from some participants was excluded from subsequent analysis because they had not viewed the training intervention.


Also, each domain s I/O device should be independent.

this complete isolation model is too restrictive for a modern mobile platform due to a simple reason: the engines on a mobile platform have to communicate and share resources with each other.


The architecture shown in Figure 2 is replicated at every decision center.

in our current implementation based SHER [1], within a given decision center, the expressive DL knowledge base is not distributed.


For instance, recall that RBAC1 was able to implement many interesting g-SIS workloads while maintaining strong security guarantees.

the complexity required for these implementations to maintain this set of properties resulted in loss of atomicity when executing certain actions, increased state size and state management overheads, and (ultimately) a loss of the elegance of the original workload.


In our evaluation, we were able to show that all proposed schemes outperform the ideal ob ject when considering ciphertext-only attacks.Moreover, in case of known or chosen plaintexts, while the random o.set addition cannot provide any security features anymore, the proposed random subrange selection and random uniform sampling schemes mostly improve on the ideal object .

the obtained results clearly suggest that further improvement is possible in di.erent directions.


We attach a thin aluminum antenna to the back of each tag to measure the .eld strength, using an Agilent DSOX2024A 1 The exact amount of harvested power is not given in [21].

it is expected to be much lower than 30 mW, due to the load-source mismatch and the loss on rectifying and regulating components.


For this purpose, the role engineering discipline [6] has been introduced.

identifying roles from scratch is a complex task.


(0), but node u will detect this attack by over i hearing node vi s transmission.Node vi is required to erase ski after it has done the forwarding for node u,which is important to prevent ski from being disclosed if node vi is compromised later.After the cluster head c receives all shares, it re-constructs S.The cluster head can send back a DONE message authenticated with S, which allows node u to detect if the established pairwise key is correct.Clearly, this scheme is secure when up to m - 1 proxies are compromised.

the scheme described above can be extended for establishing a pairwise key on the .y for two nodes that are more than two hops away.Its performance overhead will depend on the desired security level m.An alternative approach for establishing multi-hop pairwise keys is to use the base station as a helper [22].it is unclear if this approach will outperform our multiple path scheme.Designing a more e.cient scheme for this purpose without the involvement of the base station is an interesting research problem.


These guarantees or attacks can be hard to read and interpret even for experts and require detailed knowledge of the underlying model.

the analysis performed by the WSE Policy Advisor is more limited than formal veri.cation, and offers no strong guarantees, but its reports are easier to understand.


It is also possible to use pushdown automata (PDA) for expressing models, which have the bene.t of capturing call-return relationships, and hence are more accurate.

this added accuracy may not be fully useful, since enforcement of PDA models would require secure interception of all function calls made by a program, which is not possible for arbitrary binaries.


With that said, the true amount of observable artifacts in current Android devices could be much larger.

considering the possibility that SELinux may extend its coverage in the upcoming versions of Android, we choose to be conservative for the future e.ectiveness of our detection heuristics.


One way the hypervisor could detect this is by monitoring context switches that occur inside the VM.

in systems that support EPT, the hypervisor is no longer noti.ed of in-VM context switches.


As its core security technology, iOS provides application sandboxing but assigns a generic sandboxing pro.le to every third-party application.

recent attacks and incidents with benign applications demonstrate that this design decision is vulnerable to crucial privacy and security breaches, allowing applications (either benign or malicious) to access contacts, photos, and device IDs.


Program image su.cient for code reuse attacks but remains in static location.

the fact that coverage is necessary by no means makes it su.cient.


The feedback theory is closer to the correct model of how thermostats work than the valve theory.

upon interviewing users and looking at energy use data, Kempton concluded that the valve theory actually works better than the feedback theory.


In contrast to a .xed address, the Net.lter plugin uses the network adapter s MAC address for all packets it generates.

in normal operation, a single interface may have multiple assigned IP addresses.


Typically, the adversary is modelled by a polynomially bounded algorithm that aims to achieve a certain goal without having certain knowledge (e.g., cryptographic keys).

an adversary against a software attestation scheme can be unbounded in principle and has complete knowledge of the prover device con.guration and state.


In this case, MACE will not be able to identify kernel objects de.ned in these device drivers.

mACE will still detect these device drivers, because a number of documented objects (e.g., DEVICE_OBJECT) will be created for them and they will be detected by MACE.


Others are not intended but present due to the density of x86 instructions and the feasibility of unaligned execution.

unlike ROP, where a ret gadget can naturally return back the control based on the content of the stack, a jmp gadget is performing an uni-directional control.ow transfer to its target, making it di.cult to regain control back to chain the execution of the next jump-oriented gadget.


The key idea is to identify the context of the password and randomly produce tokens that match it.

it is important to keep two requirements in mind.


As our experiments show, this is true for a large fraction of malware after all, malware often attempts to interfere with or modify the execution of legitimate programs or the OS, or, at the very least, establish a foothold on the system.

it is conceivable that certain kinds of malware do not tamper with the integrity of the system.


Perhaps the closest work to Aquarium is our past work in augmenting existing human-verified blacklists by using shingling (a popular near-duplicate detection algorithm used by search engines) to compare a given page to known phish [39].

aquarium looks at techniques for improving the verification of blacklists in the first place.


the active role for the session) user to session.

while the authors do not make this explicit, they need to step outside of OWL and add rules to specify separation of duty and prerequisite constraints.


By changing the numbers of the system call, the injected code executes a random system call that leads to a completely di.erent behavior or even an error.

brute force attacks to get the new system call numbers are possible since their number is limited.


The Transformed Value Transformed Extrema Values 0.02 0 -0.02 0 0.5 1 1.5 2 2.5 Sample Number x 10 IncomingRtpReader is responsible for RTP depacketization, media decompression, and media playback; and CaptureRtpRea der is responsible for microphone capture, media encoding, and Figure 9: Original Extrema Samples (top) and its Transformed RTP packetization.

for media processing, the whole me-Values (bottom) Amplitude 0 Amplitude -1 0 0.5 1 1.5 2 2.5 Sample Number x 10 5 Figure 10: Cover Carrying Covert Media dia packets at the SBC located at the edge of the VoIP service provider s network.


Thus, the integrity of the Pedersen commitments is assured.

the service provider does not learn anything about the actual values of the transaction attributes.


PLUTUS[17] introduced the concept of lockboxes which is used to group .les with similar access parameters and key rotation to e.ciently manage data sharing and revocation.

it requires out of band communication for key distribution.


The setuid-root programs run at integrity levels {u} when they are executed by a non-administrator u.

the default policy will forbid them from performing system critical operations that require the integrity level T. most of these programs need to perform such high-integrity tasks.


A function de.ned in one domain will not be called by code in another domain, so there is no ambiguity about which domain is performing an action when the same-origin security checks are applied.

using the data-passing technique described in Section 3.1, functions can be passed between domains.


If a newly-hired employee gets added to the database,thenthe responsetothisquery will automatically includethe new employee without any changestothequery or to the policy, and is therefore dependent on the current database state.

this re.ective capabilityislimited: it cannot express a policy such as the manager of each department may update the salary data for each employee in that department without de.ning a separate view.


VPFS reuses untrusted storage in a legacy OS to store .le-system contents persistently.

there is also data that must remain in trusted storage: (1) the secret encryption key and (2) the reference hash sum for validating .lesystem integrity.


The latter practice may seem more convenient and with the least administrative overhead in terms of maintaining the list of cooperating domains.

problems arise when a policy is not tailored to a speci.c domain s design and structure, allowing an adversary to take advantage of it.


if t= p, then s = i=1 (i) (i) F2,i(K2,i, t) .


If User has successfully con.rmed his location and all activated roles are still enabled, then no action is necessary.

if thecon.rmationfails, orthe ActivatedRoles has changed, a number of possibilities arise.


De.nition 4 shows the simplest form of a cost function.

a more complex function may include in its domain other elements which in.uence the administration cost.


Even though the maximum CPU share initially assigned to each domain is 50%, the TcN1 line shows that Domain0 takes over 60% of the CPU share to process the I/O requests from Domain1.

cPU usage dropped to less than 30% by enforcing I/O ACM with the CPU usage limit of 20% (TcN2).


The problems these tools tackle are faced daily by professionals involved in reverse engineering, vulnerability detection and exploit development.

in general the solutions presented have not permeated into this industry.


In many cases a never-before-seen key with a never-before-seen email address will be legitimate.

the new address might be an attacker trying to execute a phishing attack.


In these schemes, there is only one secret key per class, key derivation is a chain of SIFF function applications which can be implemented using polynomials.

additions and deletions in [52] require rekeying of all descendants and in [53] all descendants should be rekeyed when a node is deleted.


Our model has no obvious merit comparing to the other model.

our model can detect malicious peers and prevent the malicious behaviors in a certain extent.


Watchdog [28] mechanism (extension to DSR [22]), implicit ACK in M2RC [29], and local monitoring in DI-CAS [25] detect misbehaving nodes in this way.

this kind of simple overhearing schemes does not guarantee reliable delivery, either.


While the inter-quartile range is small, there are signi.cant outliers.

none of the addresses exhibit a latency larger than one second, indicating non-ARP based operation.


, we have that .i may depend linearly on a.

by the simulator s choices at setup, recall that q(xi)= .xi .


Many image descriptors have been proposed over the last decades: one of the .rst and most used descriptors is the the Harris Corner detector [16] introduced in 1988.

recently it has been replaced by more complex descriptors that are insensitive to scale and rotation (to a certain extent).


In its current guise, the method we propose is primarily useful for step-up and backup authentication due to the relatively long engagement needed from the user to obtain su.ciently low error rates.

our implementation should be seen as a proof of concept showing that one can attain low error rates without need for specialized hardware and without relying on user recall.


The jammers may possess high computational capability to perform real-time online analysis of intercepted signal.

due to the nature of DSSS communication (i.e., each bit data is transmitted through a sequence of pseudo-random chips), it takes time for a jammer to parse the chips for any 1-bit data to determine the spreading code.


These approaches have been applied successfully in some applications such as .nding common path-ways in biological networks [49, 50] and ontology alignment between Citeseer papers and DBLP papers [22].

these networks are of smaller scale compared to social networks and more investigation is needed for large-scale social networks.


Incremental HMM (IHMM) further improves the training time of HMM.

both HMM and IHMM still have the problem of high false positive rate.


For example, if proportional fairness is adopted for power allocation, i.e., allocating power proportional to the clients reported quality of links, the same technique to forge CSI with a higher magnitude can also be used by the attacker.

if proportional fairness is adopted in the same way as in LTE for user scheduling [32], monotonically increased CSI can also gain slots unfairly allocated to that attacker.


Traditionally, we protect documents using access control policies.

these policies do not operate over provenance which takes the form of a directed graph [4].


It might seem that there is nothing to argue for sessions on which p = p, but this is not the case: In a standard password-authenticated protocol (PAKE), the attackers indeed win if they guess the password on any session.

we have n servers, and an adversary who corrupts t ' = t of them needs to use the correct password on t - t ' +1 sessions with distinct uncorrupted servers in order to break the scheme.


By de.nition, these schemes do not allow the servers to search directly over the contents, therefore their functionality is far from what an ASE scheme is aimed for.

an ASE scheme ful.lls the purpose of these index-based ASE schemes.


ASLR combined with PointGuard and canaries could make the attack slightly harder: because the original value of the frame pointer is not known, it is not possible to directly .gure out the key from the encrypted value stored on the stack.

when multiple pointers are stored on the stack, this could simplify the attack.


Often stated as another countermeasure, XML Schema validation can also help detecting SOAP message modi.cations used in a signature wrapping attack.

current Web Service frameworks by default do not perform XML Schema validation, mainly due to the performance impacts of the validation process.


Although these seem to have been designed with digital-rights management (DRM) applications in mind, it may be possible to use the same mechanisms to enhance security in a different application domain.

using a full-featured block cipher such as DES or AES in our system is likely to prove too expensive, even if it is implemented inside the processor [36].


Capacity Improvement Scheme The simplest idea for capacity improvement is to increase the number of coefficient to be modified, such as modifying the last two coefficients AC6 and AC7 instead of AC7 alone.

the direct application of this idea will surely cause much larger visual distortion considering the high amplitude of ACmax.


Bucket-based indexes limit exposure to inference thanks to collisions as, when observing multiple occurrences of an index value, the user remains uncertain over which of the di.erent colliding plaintext values corresponds to each occurrence.

the user can establish with certainty that the index value does not correspond to certain plaintext values.


This is very useful when digital signatures are used for contracts or commerce transactions, where conditions must be enforced in case of dispute.

this feature raises important privacy issues.


Another early method is Talking to Strangers [2], that uses infrared (IR) communication as the OOB channel and requires almost no user involvement, except for initial setup.

this method is deceptively simple since IR demands line-of-sight alignment and its set-up requires the user to .nd IR ports on both devices not a trivial task for many users and align them.


Classification Accuracies of the Experiment BLN-Host/Network Based BLN-Network Based Hybrid-Host/Network Based Hybrid Network Based Total Cases 65,505 62,047 65,505 62,047 Correctly Classified 65,019 59,734 65,238 61,631 % Accuracy 99.26% 96.27% 99.59% 99.33%   The results shown in Table 1 reveal that both approaches to classifying the types of traffic flows contained within the data set produce very accurate responses.

there was a noticeable gain in classification accuracy for the network only based analysis between using a pure BLN versus the Hybrid system.


If the application contains malicious functionality, the market dynamic analysis will detect it and reject the malicious application.

as mentioned earlier, malware authors often attempt to evade the malware detection system using logic bombs or by not executing malicious code when running in a dynamic analysis environment.


Such an app needs to operate in a stealthy way to visually conceal its presence from the user and also minimize its impact on a smartphone s performance.

the adversary has the resources to analyze the data gathered by the app using publicly available background information, for example, through crawling the public information released by social networks, searching Google Maps, etc.


to illustrate our proof we use a more mathematical notation.


Together, they build a trusted and secured technology stack.

the complex policy con.guration mechanisms at every single layer also represent the biggest stumbling block for a rapid adoption.


According to Figure 4, the e.ect of Semi-colon and Right Parenthesis can be interrupted as so good in terms of µ for various ß.

if Single Quotation is added on S12 to convert into S21,its detecting performance is decreasing especially around ß =1.0.


The tag helps the adversary authenticate by disclosing useful information in o.ine phases.

the tag should not reveal trivial information like the secret key.


For this, TruWallet sets the new password to pwnew := HASH(pwold ,r), where pwold is the password chosen by the user and r is a random value.

a fully automated generic approach to change passwords which works for any website is unrealistic, given the enormous variety of different procedures employed on the Internet.


Without loss of generality, suppose U ' = {u1,··· ,ut},where t=k.As (ui,rj ) .UR if and only if ej .Si, the union of {S1,··· ,St}is S. The answer to the set covering problem is yes .

if k subsets in F cover S, without loss of generality, assume that k i=1 Si = S.From the construction of UR,users u1,··· ,uk together have membership of all roles in {r1,··· ,rn}.


Human-seeded and automatic methods [13,15-18] were explored to predict click-points in PassPoints with a good success.

these fine prior art did not bring out the concept of building a model of image point memorability.


When it comes to message delivery, what happens within mp-Cloud is that the device makes a socket connection to the cloud server, providing it the device s identity information to get messages, as other messaging services do.

different from GCM, in which the server will check both the registration ID of an app and the Android ID/device-token of a device before pushing messages to the app, mpCloud solely relies on the client ID to identify a device and the app running on it.


The only operation that can be performed is to create a new role that is a superset of the permissions in the analysed roles and create relationships with the original roles.

doing so would increase the metric by increasing the number of roles and also increasing the numberofedges.


For example, prior attacks are only applicable to the scenarios where either the destination web server or the exit relay is compromised.

our attacks can be carried out by ISPs or other local tra.c observers.


In order to perform mutual authentication, we provide secrecy in addition to authenticity, hence a strong OOB channel.

the sound channel is bidirectional, and therefore, does not require the additional secrecy property.


SMash addresses earlier problems of using fragment identi.ers caused by browsers allowing complete navigation of other frames, even of different origins.

it extends the fragment messagingprotocol withashared secrettoensure linkintegrityand prevents frame-phishing with a combination of eventhandlers and messagesduringframeunloads.themessagingprotocol inversion1.1 ofOpenAjaxwasvulnerable toanattackdiscovered byBarthetal.


DISCUSSION AND FUTURE WORK We do not dispute the fact that our experimental setting was arti.cial.

we tried our best to achieve realism in our experiment.


Even if a service provider is offering a bring your own phone" (BYOP) service, the con.gured device is learned and recorded against the user account during the account activation process.

calls from unknown devices are blocked and such devices are treated as unauthorized devices.


This minimizes the threat posed by external attackers.

since a number of ports must be open to allow the Grid to function, it still remains possible for an attacker to compromise the Grid headnode (1.1) and from there to attack the cluster (1.2).


We expect Robusta should be able to sandbox most of JDK s system libraries, as we have demonstrated for zip and libec.

it ispossible that not all native libraries for system classesare suitablefor Robustabecauseofrestrictions related to functionality or performance.


Thatis, these users can read anydata stored on thedevice.

they cannot extract thedatafrom memory to external storage.


Only permitted IP packets may pass through the fire-wall or the NAT much like only people who have the key may pass through the door of the house.

when a host in the LAN is compromized by a malicous bot, it is hard to identify the compromized host from the outside of the LAN, much like it is hard to find a robber who is hidden in the house or the building.


While we could traverse kernel data structures (e.g., task_struct) to retrieve such information, our approach is to inspect the system call arguments (e.g., the argument of execve(2)) of process creation to make our system more OS-agnostic.


A key component of a router is the routing table which determines which output port an arriving packet should be forwarded through.

because of the .exibility (or programmability) of the routing tables, we show that it can result in security vulnerability.


Since smart mobile devices are also used in emergencies [21 23], they can be also used to compromise the safety of emergency responders and evacuees [24].

signalling storms are caused by misbehaving mobile apps that frequently set-up and tear-down data connections, as exempli.ed in [25].


A trivial de.nition for a risk-assessor is to .x an uncertainty threshold below which all decisions are deferred to the central policy, and above which all the decisions are taken locally.

in general, di.erent requests have di.erent potential impacts on the system.


To accomplish this, we are required to have a detailed understanding of the behavior of the servers.

a server initialization process has complicated steps, such as reading con.guration .les and linking libraries.


A user may possess multiple credentials certifying different attributes of the user.

such credentials may not be accepted by the service provider with the same degree of trust.


In contrast, up to 16 TB requires only L = 3 levels of recursion.