Unfortunately, also high-interaction honeyclients have limitations.

an attack can be detected only if the vulnerable component (e.g., an ActiveX control or a browser plugin) targeted by the exploit is installed and correctly activated on the detection system.


We formally cover these assumptions by modelling Read, Gen and Chk as oracles.

whenever P wants, e.g., to execute Read(State(P), a), P sends a to the Read-oracle and receives the corresponding result s. While sending and receiving messages between P and the oracles are modelled to take no time, the determination of the response does.


{0, 1}n × {0, 1}n Sj is the set of pairs of strings a, b so that a and b are disjoint except possibly on the jth coordinate.


This can give a strong advantage against raw parsers which do not decompress objects contained inside a PDF .le.

figure 8 shows 4without user interaction.


This is an aspect with which Kessler s approach cannot be said to be less restrictive than Brewer-Nash.

there exist authorization states that satisfy the Chinese Wall security policy that are unreachable under Kessler s approach that are reachable under Brewer-Nash.


Then Q is a valid type 1 forgery if and only if (g) m = s¯0 = s 0; and e N (h) (¯s0 - s 0) + (¯ci - c i)ai = 0. i=1 Therefore, if A can produce a valid type 1 forgery Q, then it would be able to learn (g) and (h).

a can determine f possibilities of a, say a1, .


We capture the state of being identity-less by the null pseudonym  8.

for an identity-less event e we have id(e)= 8.


This is the same issue that we considered when letting students play adversarial roles [11].

aren t we providing adversaries with malicious ideas when experimenting with security-sensitive technologies, designing adversarial aspects into such experiments, and trying to learn from those?


We show that privacy and error-resilience are contradictory goals.

we show that for every constant c > 0, there exists a function f which is privately computable in the error-less setting, but for which no private and correct protocol is resilient against a c-fraction of errors.


(A trie can be viewed as a tree-structured .nite-state automaton for matching strings.)

when a variable v is encountered in the trace with value s, we traverse down a path in the trie that matches s. If there is a complete match for s, and this match takes us to a state S in the trie, then the variables associated with S are candidates for equality with v. Each variable v ' associated with any descendant state S ' of S is a candidate for the relationship prefix(v, v ' )= v and prefix(v, v ' )= s. Similarly, any variable v '' associated with an ancestor state S '' '' '' of S is a candidate for the relationship prefix(v, v )= v and '' '' prefix(v, v )=s '' ,where s is the string corresponding to state S '' ''' .


Equation (7) is the corresponding utility function for network threats: V = 200,000 -10*Y (7) Note that the multiplier of X or Y is greater than one.

for each dollar invested in the countermeasure the benefit is greater than the amount of investment.


Not surprisingly, eye trackers are optimized for eye tracking, and the iris images they acquire are not well suited for iris recognition.

eye trackers have a relatively wide field of view to allow continued tracking even when the user moves his or her head.


Assume Im = {i1, ..., ik} is the set of indices of those meters.

the attacker can modify zij ,where ij .Im.


There are current data sets that have mobility and geolocation data for large groupings of people over large metropolitan and campus environments.

the cellphone data set used by P.Wang et al.


First of all, the number of friends can in.uence the applicability and the usability of SA.

users with many friends may .nd it dif.cult to identify them, especially when there are loose or no actual relationships with such friends.


Furthermore, this paper has argued that there is a trade-off between accuracy and security in case of two-factor biometric authentication.

in two-factor biometric authentication, the better the accuracy in case of secure key, the worse the security if secure keys are compromised.


Step 1: We perform the initial allocation to maximize the total achievable data rate, without considering constraints (10) and (11).

each subcarrier is assigned to the user who obtains the best channel condition.


This gives a pretty good picture about the impact the check can have on such channels.

for the intent channel, we measured the time interval between the invocation of startActivity and the execution of performCreate (the first API the target Activity needs to call).


This allows us to demonstrate that there are quantitative and intuitively clear consequences of diversity when defending the CIA goals against both single and multiple attackers.

it is shown how the probabilistic security properties of components relate to the security properties of systems built out of those components.


Statistical Profiling and Visualization for Detection of Malicious Insider Attacks on Computer Networks  Jeffrey B. Colombe The MITRE Corporation Emerging Technologies Office McLean, VA (703) 883-5307 jcolombe@mitre.org ABSTRACT The massive volume of intrusion detection system (IDS) alarms generated on large networks, and the resulting need for laborintensive security analysis of the text-based IDS alarm logs, has recently brought into question the cost-effectiveness of IDSs.

when host-based IDSs are used to monitor an organization s internal networks, the majority of the resulting alarms represent legitimate, automated system administration.


Our core security calculus is simpli.ed, although we take care to include all aspects that require conceptual modeling for reasoning about DFI.

we model threads, mutable references, binaries, and data and code pointers; other features of x86 binaries, such as recursion, control .ow, and parameterized procedures, can be encodedinthe core calculus.Wealso modelall detailsofWindowsVista that are relevant for mandatory integrity control with dynamic labels.


They are less popular though because malware is usually well-protected against static techniques.

today s malware programs leverage code obfuscation[24], code encryptionand runtime packing[18] to makedis-assemblydi.cult.


For the recognition of a shape password, the strokes do not have to be connected, which in consequence means that an unlimited amount of stroke combinations is possible.

a shape password can consist of several single shapes (e.g.


We interviewed each user again after one month, and then every four to eight weeks, depending on user availability and activity.

we scheduled interviews shortly after users created delegations, to ensure that they would remember the reasons and context behind the delegation.


It is necessary to take the latter approach to avoid compro- mising the security of our protocol.

if d is split multiplicatively, the cosigner is able to create multisigna- tures on his own without the help of theprimaxy signer.


The creation of the Web Cryptography API has been heavily in.uenced by prior academic work such as the Stanford JavaScript Library, but also presented a number of hard practical questions where empirical research is needed [6].

we need to better ascertain the ability of developers to use cryptography APIs in general.


mines that to reach the goal state (i.e., root level access on C) in c3, an attacker either needs {s7,s8,s9,s2,s3,s5}or {s7,s10,s11,s12,s14,s15,s17} attributes to be satis.ed in the initial (start) state.

two distinct attack paths are now available for an attacker (in c3), instead of just one attack path (as in c2).


Although various identity management systems supporting Single Sign-On would minimize the number of passwords a user has to remember, it is unlikely that all the services a user wants to use would rely on the same trust domain.

a user will need to be able to authenticate to many di.erent trust domains.


This extension is the basis for a model-driven development approach supporting role-based access control policies with break-glass.

our approach supports the generation of break-glass SecureUML policies for a concrete security architecture based on Java and XACML.


MAST develops a perception of suspicion for applications through the use of Multiple Correspondence Analysis (MCA) [1], a technique used in the social sciences to determine the statistical correlation between multiple categorical (i.e., qualitative) data.

we develop a questionnaire for Android applications that looks for strong relationships between declared indicators of application functionality (e.g., permissions, intent .lters, the presence of native code, etc.)


A minimum disclosure D corresponds to a solution S ' for the corresponding minimum set cover prob lem.

each disclosed credential corresponds to a subset in S ' .


This means that a candidate password can be excluded if two or more pass-pictures in this candidate password appear in a public challenge.

observation of one public challenge can lead to a reduction of the password space.


CFS is a virtual .le system that runs at user level on the client machine.

it mainly performs the .le encryption and key management functions and leaves the rest of the functions to the underlying .le systems.


Another interesting aspect that has not been addressed yet is the behavior regarding multiple PassShapes.

will users be able to remember several different PassShapes for different purposes?


In the AdaBo protocol, we optimize the way the booking part of the memory is used.

all the memory dedicated by the AdaBo to the adaptive approach will be considered as SMSs.


However, for L to actually approach the worst-case logn, the block size needs to be close to 2 · logn.

with 512 byte = 4096 bit blocks, we would need a disk holding 22056 bytes to approach that many levels of recursion (4096 = 2 · log n, so n = 22048 blocks, each of size B =512 byte.


M is the entry point of e, e does not transition to an authorization error state; insuf.cient otherwise.

for P to be suf.cient, it is necessary that no execution transitions to an authorization error state, provided the user has permission to initiate the execution by calling its entry point.


However, in our protocol, User only initiates the protocol.

a malicious User ' cannotinitiatetheprotocol with atargeted User.


If security against non-adaptive attacks is suf.cient in some scenarios, then one round in EK (·) could be reduced.


In what we call the full black box model, the PKG is given access to decryption queries and no assumptions are made regarding how the decryption box works.

just by observing the input/output behavior of the given decryption box, a judge should be able to decide if the box was created by the actual user or by a dishonest PKG.


During regeneration, a majority voting scheme is applied to each of the columns in the three identically regenerated bitstrings as a means of avoiding single bit .ip failures.

the .nal bitstring is constructed by using the majority of the 3 column bits as the .nal bit for each bit position, i.e., a 1 is assigned in the .nal bitstring when 2 or more of the 3 bits in the column are 1 , and a 0 otherwise.


Thus, it is di.cult to obtain an overview concerning who is allowed to do what.

this makes it di.cult to provide a sound audit function (see also [10]).


A more generic detection of JavaScript attacks is achieved by the systems Blade [17] and Arrow [28], which identify attacks using indicators outside the browser environment.

blade spots and blocks the covert installation of malware as part of drive-by downloads, whereas Arrow generates detection patterns for the URLs involved in JavaScript attacks.


To evaluate the primitive level performance slowdown, we use the standard micro-benchmark LMBench suites to estimate the VMI s impact on various OS operations.

we focus on the overhead that instrumentation introduces to context switches, page faults, memory-related operations (such as memory map), and IO-related operations (such as TCP and disk .les).


However, it is important to note that if bar was empty (and certain other conditions satis.ed), then it would have been removed.

there exists some argument such that ext2 rmdir performs the conceptual operations shown in Figure 5(B).


Resilient Multidimensional Sensor Fusion Using Measurement History Radoslav Ivanov Computer and Information Miroslav PajicDepartment of Electrical and Insup LeeComputer and Information Science Department Systems Engineering Science Department University of Pennsylvania University of Pennsylvania University of Pennsylvania Philadelphia, PA 19104 rivanov@seas.upenn.edu Philadelphia, PA 19104 pajic@seas.upenn.edu Philadelphia, PA 19104 lee@cis.upenn.edu ABSTRACT This work considers the problem of performing resilient sensor fusion using past sensor measurements.

we consider a system with n sensors measuring the same physical variable where some sensors might be attacked or faulty.


For our implementation, we restrict ourselves to a twovalued OCL-like language for specifying SecureUML permission constraint, i.e., we only support calls to public attributes and the result of calling sidee.ect-free public operation of the current resource (object),  the special SecureUML keyword caller referring to the subject executing an action,  a limited set of functions for comparing values, e.g., _=_, _ <= _, _<_, and  the Boolean operations _ and _, _ or _, and _ not _.

we do not support recursive OCL expressions and iterator-based expressions like ->forAll( _ | _ ).


The uniqueness results show statistical behavior consistent with law of large numbers and comparisons of bits derived from random processes.

non-divergence of Gaussian mean values and Gaussian standard deviation values were demonstrated when the number of response comparisons was increased from a relatively small number of about 1 million, giving a high degree of confidence that chip uniqueness from a statistical standpoint is guaranteed as the number of comparisons increase well beyond 1 million (the Gaussian tail is very well behaved and does not flare out or show divergence).


The main feature of such protocols is that they attest speci.c properties of the software platform.

instead of attesting software using low-level measurements (i.e., software hashes), which could reveal proprietary information to competitors, they attest whether the software satis.es certain properties impliedby the client s security goals.Forexample, on SSC, such protocols could attest that the hypervisor implements the SSC privilege model,but not reveal anyadditional information to clients.


The W.X hardware support allows to mark a memory page as writable or executable, but not both at the same time.

it will prevent kernel rootkits from injecting rootkit code as data into the OS kernel and later executing it as code.


Convertible un- deniable signatures [11, 19, 28] require the signer's assistance for verification, but have a feature that allows the signa- tures to be converted into "un~ersally verifiable" signatures.

the original signatures can be converted into signa- tures that can be verified by anyone without the assistance of the signer.


We repeat to perform all operations that could be performed.

we loop through all such statements and repeat the loop whenever the last loop results in a new successful assignment.


In this paper, we explore the approach towards a more .exible and adaptive control through the incorporation of risk awareness in SC.

risk values are associated with users and objects; meanwhile, risk thresholds are de.ned for each of the permissions.


The latter usually focuses on attackers actions detecting or preventing them while the former focuses on attackers perceptions manipulating them and therefore inducing intruders to take actions/inactions in ways that are advantageous in relation to targeted systems.

traditional security controls position themselves in response to attackers actions while deception-based tools are positioned in anticipation of such actions.


Nonetheless, useful features contribute positively to the .nal score, especially for samples where the anomaly value determined by necessary features is low (this is the case for scores represented in the lower left corner of the graph).

without the contribution of useful features, the anomaly score of seven samples would be below the threshold (i.e., they would be false negatives).


However, even selective .ltering does not guarantee that the rate of bus tra.c collected is steady and expect-able.

a deluge of meaningful information may coincidentally congregate within a short period of time, overwhelming the computing power of Veri.er.


4.1 Prevalence of the Botnet Phenomenon In order to provide a high level view of botnet prevalence, we highlight the contribution of their spreading activity to the overall unwanted traf.c received at our darknet space.

we examine to what extent the traf.c received at this viewpoint can be attributed to botnets spreading activity.


We adopt a one-dimensional, linear, discrete view of time, with a beginning and no end point.

the model of time that we choose is a total order of time points that is isomorphic to the natural numbers.


The ability to compute these aggregates is dependent upon whether a singly homomorphic encryption scheme or a fully homomorphic scheme is used.

whether one or two operations with ciphertexts with the homomorphic property are performed.


In other words, p is a plan for C if and only if it is a plan for .1 .···..c for some .i .Gi, where .i is a Type 1 constraint and .1 .···..c represents the constraint set {.1,..., .c}.We call .1 .···..c a simple constraint expression.

we have reduced the satis.ability of an instance of WSP3(=, =) to determining the satis.ability of one or more instances of WSP1(=, =).


Finally, with namespace-based covert communication detectability mostly depends on m and on the size of the covert.

a higher value for m implies lower detectability: less content packets have to be requested to write and read a covert message.


At this point, we can only make these claims intuitively.

proper evaluation of the usability requires a signi.cant number of factors concerning the interface design.


Recent work [33] has considered exploiting the GPU s massive hardware parallelism and high-bandwidth memory system in order to implement high-throughput networking operations.

a handful of proposals [19-23] have looked at accelerating regular expression matching on GPU platforms.


Our attack can be easily adapted to break this variant: In the .rst stage, we recover the noise space but ignore the free term.

we recover two polynomials v, v ' but instead of having g = a · v + b · v ' for some scalars a, b,wewould have g = a · v + b · v ' + c ·(1, 0,..., 0) for some a, b, c (and similarly for h).


In particular, we explore tradeo.s between con.dentiality and availability in such systems that suggest improvements in one may come at the expense of the other.

there is No Free Lunch in cyber security.


However, the encryption of the CertU ensures that RsM is restricted to only the pseudonymized identi.er IDU .

if the attacker discovers which user had possession of a particular User device at a given time, he could discover the identity by pairing the user with the associated IDU .


In the event handler, we use the if statement in Bro s scripts to select what commands need further physical analysis.

the physical analysis is implemented by connecting the Master IDS to the power flow analysis module included in Matpower [10].


As noted above, there exists a gap between a privacy breach and di.erential privacy.

the pollster may release data that violate di.erential privacy, but do not lead to a privacy breach.


Several recent work [7, 15, 18, 22, 24] recognized the need of joint management for data sharing, especially photo sharing, in OSNs.


We modify the renegotiation information extension to include an additional value, the .ngerprint of the encrypted messages sent over the previous phase s record layer.


is chosen so that the dictionary size is 1 7 of the keyspace (i.e., 86% of sequences are ignored), then a sequence generated according to the model has the probability of 90% of belonging to the dictionary.

15% of the password space contains 90% of all plausible passwords.


In exhibiting attacks that require no other affordance than the system call API, we focus attention on this API as the crux of security in this setting.

even a perfect defense mechanism that makes the kernel an untrusted peer to applications is not, by itself, suf.cient to secure these applications from attack.


The integrity of a VE is still monitored and protected but with drastically reduced overhead.

our framework, termed Journaling Computing System (JCS), makes the following novel contributions.


Table 8 shows the different views defined by the model, and how they were applied and validated for each of the concepts.

all views applied for Benefits and four of them were validated in [5].


The key thing to note here is that MyPageKeeper identi.es so cial malware at the granularity of individual posts, without group ing together posts made by any given application.

for every post that it crawls from the wall or news feed of a sub scribed user, MyPageKeeper s determination of whether to .ag that post does not take into account the application responsible for the post.


In the context of TMS, the need to protect the privacy of search operations, minimize data exposure during a possible attack on the TMS infrastructure and, at the same time, a requirement for fast and efficient operations, led to the employment homomorphic encryption algorithms [10] in the solution architecture.

two partially homomorphic schemes were deployed: Search Scheme [11], a homomorphic encryption scheme designed for text data, allowing equality comparison between encrypted keywords of an email message or query.


The set of rules in.uences the policy and ultimately the whole system behaviour.

a single rule will result in a grant, reject or error decision and the .nal decision of the policy will be based on these decisions.


EFFICIENT T-PAKE FROM PPSS A password protected secret sharing (PPSS) scheme can be used as a black box to achieve a threshold password authenticated key exchange (T-PAKE) protocol (in the public key model) at very little additional cost.

the round complexity of the resulting T-PAKE is the same as the PPSS because all the T-PAKE messages can be piggybacked onto the PPSS protocol .ows.


CREATE VIEW Courses_View WITH pAS_key, pRoll_keySELECT * FROM Courses_Table WHERE Authorize(:pAS_key, :pRoll_key) IS NOT NULL Figure 15: course parameterized view definition The idea of this definition is to allow only the application s users to access the table.

it is not enough to connect to the database with the DB user, in order to access the table, but you also need to be one of the legal application users, so that you can access data.


When a policy P1 is changed to become a new policy P2 that cannot totally replace P1 it can be important to identify those running instances that are in states which are not affected yet by this change.

the change affected only parts of the policy that these instances have not yet reached.


Secondly, without a matching ngerprint, an attacker should not be able to obtain any sensitive information from the card.

users private keys must be stored in an encrypted format.


Things are quite different in the RF domain.

in order to test data-level GPS attacks via RF, we need to be able to generate and broadcast our own GPS signal just like a real satellite.


In such systems, the processes will always respond to any input with full honesty.

the system s responses are always trusted and fully represent the internal state of the system.


For the .gures, we aggregated the probability values (which are real numbers in the interval between 0.0 and 1.0) into ten bins, each bin covering an interval of 0.1.

all probabilities in the interval [0.0, 0.1[ are added to the .rst bin, values in the interval [0.1, 0.2[ are added to the second bin, and so forth.


More permissions can be granted than developers intend.

permissions that allow a site to post to the user s pro.le are granted on an all-ornothing basis.


For the sake of space, the equations for G/G/1 are not given here.

if DRL is sent by beacons -the periodic broadcasting packets, the length of the RL stored at a user can be modeled as D/D/1 queueing system.


Remarkably, although locality constitutes a strict constraint on the structure of LGI laws, it does not reduce their expressive power, as has been proved in [6].

despite its structural locality,anLGI law can have global effect over the entire L-community mostly because all members of that community are subject to the same law and can, thus, be used to establish mandatory, community wide, constraints.


6.3 Advanced Security Features Advanced ob jectives such as secure delegation (O6) and policy-based access control (O7) require a secure user interface to handle security-sensitive user input (as discussed in Section 3.2).

token delegation relies on a password-based authentication of the delegated user U against the car owner O before the delegated token is issued.


From that point, our query engine essentially plays the role of a botmaster.

for a given bot, we learn how to correctly mimic its behavior in the wild by subjecting it to a barrage of commands.


Phase I: Trace Collection Trace Collector Web Server User/ (WebScarab Proxy) Simulator Session Inspector Session Exporter Phase II: FSM Inference SessionProfile Web request /response Spec Analzyer Symbolizer RequestProfile Session Variable TemplateProfile Session Log FSM Analyzer DriverSpec StateProfile TestSpec Generator TestSpec Phase III: Testing Testing Engine Web Ser ver State Driver Testing Controller Symbolizer Session Inspector Session Exporter LoginProfile Request Generator Output Evaluator Login Helper InputProfile Figure 4: Prototype System Architecture Testing Engine instantiates test input vectors into concrete web requests (i.e, Request Generator ), feed them into the application and evaluate the corresponding web responses for vulnerability identi.cation (i.e., Output Evaluator ).

testing Controller is in charge of the entire testing procedure.


We are currently applying some of these approaches to establish their effects, whilst the others are promising avenues for future research.

we suggest a three-tiered approach to address the current state of affairs: 1.


However, HIP-based approaches have inherent drawbacks.

they are too obtrusive to be tolerated by human players in a gaming context.


EVALUATION This section discusses our approach to validate the proposed models and to evaluate the detection e.ectiveness of our system.

we assess the capability of the models to accurately capture the properties of the analyzed attributes and their ability to reliably detect potentially malicious deviations.


4.1.3 Limitations Green Button has been developed only for information exchange, and therefore it de.nes only the data model.

authenticity veri.cation and privacy preservation are not in its primary scope.


It contains a sub-model to present trust relationships among system entities, a sub-model to specify the information related to trust management for a software component, a submodel for trust evaluation and a sub-model for trust management.

trust involves two entities: a trustor (tr) and a trustee (te).


In this paper, we discuss how trusted platforms can be used in trust management for web services.

we move forward from the notion of user based trust management to user and platform based trust management.


This is due, in part, to the traditional view held by many policymakers, namely that technology develops autonomously.

technology is assumed to evolve according to its own internal logic, and thus attempts to bring social and ethical concerns into the actual design of technology are doomed to fail.


G) e The (f,w)subset code is a primitive batch code with n w G) we and Nmj.oj.

we index each data item by a unique G.el)set TEand each bucket by a unique subset S[f]of wsize at most w. The content of bucket Sis de.ned by: rsdef xT.each bucket receives the sum (or exclusive T:sr T w or) of the data items labelled by its supersets.


If two are the same non-gap label, then that label is mapped onto all three fragments in that position.

the three fragments are corrected over their region of intersection according to majority decoding over labels.


Withtheexceptionof thechannelbetween LD and User, we make no assumptions about the underlying network medium.

the other connections can be either wireless or wired, and weplace no restrictions onthis choice.


We present an open smartphone-based immobilizer system architecture and the underlying security framework, which provides enhanced functional and security features and overcomes the security issues of the conventional immobilizer systems.

our contribution is as follows: Framework for smartphone-based immobilizer systems.


Conflicts between NA and RA rules are avoided by construction since RA rules are defined on the view produced by the evaluation of NA rules, according to an open policy.

nA rules always take precedence on RA rules.


Our approach provides a di.erent point in the design space.

our policies are more expressive, in that our framework can handle both integrity and con.dentiality policies, and more .ne-grained, in that our framework can carry multiple taints from di.erent sources at the same time, rather than just a single bit of taint.


Firstly, we discuss the challenges of actually implementing the CL credential system on a Java Card.

we consider the severe platform restrictions, which entails concise analysis of the available interfaces as well as careful treatment of the hardware resources.


Note that the D-S theory calculates the probability that the evidence supports a hypothesis rather than the probability of the hypothesis itself.

the probability being computed is tied to confidence that a particular suite of evidence is being interpreted correctly, rather than that some particular hypothesis is correct.


TheRMPtriesto optimizetheUser-Role and Role-Permissions mappings, in a similar fashion one can optimize the Domain-Type and Type-Resource mappings within an SELinux policy.

we can optimize theDomain-SubType mappingsbetweenthedomains D and the resulting sub-types T ' .


Table 4 shows the average and median time to label a page in our two conditions.

the clustered condition offers the best average time (1.8 hours, SD=2.6 hours) as well as median time (0.7 hours), outperforming all other blacklists by a wide margin.


In the case that the parameter vector is insecure, it is also natural to define a continuous-valued security level that measures the error in the adversary s estimate.

we can define the security level to capture the adversary s estimation error, for the particular estimator he/she uses (if this is known).


In addition to the above observation, if k2 > 0 then the .rst user and if k2n < d, then the n-th user can be accused of being a traitor.

a wise traitor strategy (if the .rst or/and the n-th user is in the coalition) would try to have k2 = 0 and k2n = d. In this case, similar to  M [1, d] [d + 1, 2d] [2d + 1, 3d] .


In our approach, invariants that are true at the function call site are propagated inside the function to obtain a more re.ned control structure.

for every function call site, we might inline a different, more precise, model of the function.


We assume that adversaries may only interact with principals through trust negotiation and are limited to proving possession of attributes which they actually possess.

the trust negotiation system provides a means of proof which is resistant to attempts at forgery.


We have not yet fully automated the entire process in Figure 2.

interaction with NuSMV and the validation done by the trace-instance-validator are performed by humans.


Apple allows users to limit applications use of Location Services on a per-app basis.

when an iOS application .rst attempts to access Location Services, the operating system displays a prompt to the user and asks the user whether to grant or deny access to location information for this application.


For example, if there are one million health records in a system, atomic propositions should be used to express the policy regarding each of them which will make the system very complex.

lack of quanti.ers and predicates may lead to scalability issues in formalizing policies.


In addition, it requires that only the certi.er of a TP (i.e., security administrator) may change the list of users and CDIs associated with the TP.

the model enforces the principle of separation of duty between system users and system administrators.


we correctly detected 15,857 on Twitter, and after our submission to the Twitter spam team, these accounts were suspended.


Extensible Markup Language (XML) Unlike HTML, which has a predefined vocabulary of tags for displaying data, XML is designed to describe data by enabling XML authors to invent self-descriptive tags to annotate web pages or sections of text on a web page and apply arbitrary structure to their web documents.

xML is all about the description of data while HTML describes data and its presentation.


Hence it is suf.cient to con.ne our analysis to the set of rules speci.ed for a single attribute, repeating this process for each attribute in turn.

we can analyze the reachability of each attribute in the query independently and the combine the results.


We prefer pull to push because push will get malicious activities exposed easily.

under push many SMS messages are sent out from one or a few central nodes, whereas pull can be implemented in a more distributed fashion.


In other words, we generally do not even know the probability that the event may happen.

the strike time of malicious act can be considered largely random but the event is only describable post-mortem.


It is clear that UP satis.es all resiliency policies in F , and hence there exist no more than b users together have all permissions in P .

there exist no more than b elements in {P1, · · · , Pn} whose union is P .


The revocation manager maintains the revocation list and regularly publishes the newest revocation list to everyone in the system, signed using his private key.

the revocation manager publishes {priv-RL}-1 , {sig-RL}-1 , KK RR and {issuer-RL}-1 .


After testing all values, the set of possible candidates contains in average 8 elements.

the attack discards all the candidates of the byte of the key which have a corresponding fault that is not included among the possible ones considered by the model and reduces in average the set of candidates from 28 possible to 23 compatible with the model.


If we are able to precisely identify these in-VM syscall execution contexts when the corresponding trusted utilities are executed at the VMM layer, and if we are able to maintain a secure duplicate of the running VM, through redirecting both their memory read and write operation from the secure VM to the running VM, then we can transparently update the in-VM kernel state of the running VM from the outside via the secure VM.

the semantic-gap (e.g., the memory location of in-VM kernel state) is automatically bridged by the intrinsic instruction constraints encoded in the binary code in the duplicated VM.


2, Where, Trequestis trustworthiness of the peer requests to consume service, Tprovide is trustworthiness of the peer provides service, and [T ,T ],(T <T ) is the range of trustworthiness.

12 1 2 when a peer look for peers who can provide some service it need, it should look for those peers whose trustworthiness is close to it.


One of the key reasons that trusted systems are good at enabling price discrimination is that they sharply decrease sharing; they are designed to eliminate any redistribution of the information good outside of the control of the content provider.

price discrimination allows the market to extend to consumers with lower willingness to pay, but at the expense of cutting off existing means, through sharing and secondary markets, of getting the information or entertainment at low or no cost to some of those same consumers.


Sanitizing should therefore be invisible.

no one should be able to determine whether or not the disclosed document has been sanitized.1 SUMI-5 does not assure this.


In fact, the top 3 most vulnerable device types represent over 55% of all vulnerable devices discovered by our latest scan.

there exists at least 300,000 vulnerable embedded devices which can be controlled via 3 similar Telnetbased administrative interfaces.


More recently [10][11], it has been recognized that in practice, it is reasonable to assume the attacker s control over the network increases monotonically, i.e., the attacker need not relinquish resources already gained in order to further advance the attack.

at a reasonable level of modeling fidelity, attacker behavior resolves to monotonic.


Recently, several collisions were announced which decreased the security of some of the existing hash functions.

collisions were announced in SHA-0, MD4, MD5, HAVAL-128, and RIPEMD.


We propose to simply drop the requirement that v ' exer cises the same control path as v. Instead, we de.ne VR(v) to be the valuation vc that maps every integer variable to v(s) i 1 and every string variable s to a , where a denotes a string of a s of length i.

vc maps s to a string of a s precisely as long as the string mapped by v. We note thatvc is manifestlybenign andnon-attackingfor any program.


To this end, our system uses the previously-constructed CFG and identi.es all nodes associated with conditional jumps that are (i) part of the stalling loop and that (ii) have one successor node that is not part of the whitelisted code region.

we identify all nodes through which there exists a path that exits the stalling code.


CONCLUSION Through empirical demonstrations, we have shown that the characteristics of storage are fundamentally different from those of network, and cryptographic assumptions on the uniqueness of keys and IVs relative to content can be violated through unanticipated side effects from various storage mechanisms.

we have demonstrated storage mechanisms that can convert intended one-time pads into two-time pads: in-place updates, backups, inconsistencies between memory and disk content, and wear-leveling for flash storage.


The choice of adequate values for the parameters in our proposal must be done carefully, taking into account the relationships among them.

the maximum bitlength of the tree identifier of each revoked certificate, the maximum tree size takes the following value: .


1.2 Our Contributions In this paper, we describe a methodology which allows the service provider to obtain a quality measure so as to guarantee that the input to later computations and the corresponding output (the actual analysis performed on the data) comply with certain con.dence criteria.

we propose a protocol that allows evaluating the quality of ECG signals and communicates to the user whether the input signal is good enough to continue with the measurement and analysis or not.


In the case of a trusted server, it is well know that adding Gaussian noise protects privacy.

we can sanitize the output of any real-valued function f : ad logs .


As with other solutions, the security of the system can be further improved by maintaining some state between sessions.

if honest Alice and Bob establish a key without interference and eavesdropping, they can exchange along-termpre-sharedkey, and executeprovably secure and e.cient key exchange in future sessions.


We can clearly see that the targets and the activities of this army have evolved between certain attack events (e.g., when the value of zi is low).

this army has been scanning (at least) four consecutive class A-subnets during its lifetime (still 183 days), while probing at the same time three di.erent ports on these subnetworks.


Unlike the previous case, protection from denial of service is the main security goal of the PoE guest.

the PoE might accept granting access to unauthorized requests but it should not deny access to requests authorized by the PoE guest.


In this approach each neighboring node is associated with an estimated RSSI value.

after oppnet deployment when nodes perform neighbor discovery, they record the RSSI value of each of their neighbors to use them later for intrusion detection.


In xor composition, either the steps in W1 are executed or the steps in W2, but not both.

xor composition represents non-deterministic choice in a work.ow speci.cation.


We were able to manually verify that the .ve Virut .les in our set were indeed all infections of the same original executable .le.

the .ve Virut .les contained the same host .le and only di.ered in their last section wherethe actual(polymorphic) virus code resides.


The work in [16] deals with spam SMS messages that contain text in a mixture of Thai and English language words (it is worth pointing out that Thai has a completely different character set).

two di.erent .ltering methods were implemented and tested.


In this paper, we present and analyze ProActive Caching according to performance improvements and provide a detailed comparison with other approaches for caching role-based and dynamic access control decisions in business process-driven systems.

we compare generic caching strategies against caching strategies developed to speci.cally cache access control decisions, i. e., SAAMRBAC and ProActive Caching.


U} is the space of functions that map (the serial number of) each Rate invocation to the user identi.er space.

if (u, u ' , ·) is the parameter triple of the ith Rate invocation, then, for all i .


While anti-virus software will continue to play a central role in defending against smartphone viruses, it has several limitations.

the majority of existing anti-virus software rely on an up-to-date virus signature database to detect malwares.


In the Franklin-Boneh IBE scheme [12], the E xtract function takes the I D as an input parameter.

e xtract uses I D to compute QI D = H1 (I D) .


Ourexpectationsabout the advantagesof the Grid s features were borne out by the statistical results of our user study.

our study demonstrates higher accuracyfor the Grid compared toWindows for the view-complex, changecomplex, and con.ict-complex tasks that tested the Grid s whole policy, effective policy, group membership information,simplechanges,andnewpolicy semantics features.


Specifically, for the nextintent problem (Section 3.2.1), both Dropbox and Facebook informed us that an effective fix takes time to build.

dropbox explained that they need to change the architecture of their app, which involves non-trivial effort.


IMPLEMENTATION We have prototyped an end host-based Shield system on Microsoft Windows XP.

we have implemented Shield as a Microsoft WinSock2 Layered Service Provider (LSP) [16].


4.4 BehaviorAccumulation Sincethe suspicionlevelisgeneratedeverytimewindow, a worm canhideitselfby appearing benignfor each windowbut malicious overall.

it may spread suspicious behavior over different time windows or reduce the intensity of malicious activities within a single window, thus decreasing its suspicion level.


First, because PaX ASLR randomizes only the base addresses of the three memory areas, once any of the three delta variables is leaked, an attacker can .x the addresses of any memory location within the area controlled by the variable.

we are interested in the delta mmap variable that determines the randomized o.set of segments allocated by mmap().


With the exception of our implementation description in Section 6, we will assume an idealized PUF in our protocol design.

given a challenge-response pair  and another challenge Cj Ci, one cannot predict the value of Rj .


between privacy and computational overhead on one side and data reliability on the other.

instead of submitting np×nc pairs (where np is the number of physicians and nc is the number of conditions) to contribute a single recommendation, a patient might choose to submit fewer pairs for a subset of physicians and/or conditions.


A setting where this is particularly important is that of wire- less ad-hoc networking: secure communication between ar-bitrary co-located devices that share no a priori trust infor- mation other than that their owners wish them to commu- nicate with each other.

we want to capture the user intuition that they want their device to commu-nicate (only) with that particular communication partner -to have the act of pointing out who you want to talk to also implicitly indicate to the software who was authenti-cated to communicate with you.


An intra-task property characterizes sequences of actions that are authorized by the privilege assignments of a single task to the user.

an intra-task property is enforced if a user cannot violate itbyusingonlytheprivilegesshe obtainedfromasingletask.


One way to do that would be to establish a quality gate for the Debian release process based on a sound static analysis tool for format string bugs.

no package would be distributed until after a developer had resolved all warnings from a format string detection tool.


Virtualizationhasbeenusedas enablingtechnology to ensure strong isolation indi.erent researchprojects likeTerra [6], EMSCB [11] and OpenTC [8].

openTC is a research project funded by the European Commission and aiming at the development of an open-source security framework built upon TCG s security concepts.


Note that, if a client is not a legitimate member during certain period, e.g., before he joins or after he leaves the session, he should not be able to decrypt the media content.

the SK needs to be updated once a client joins or leaves the session.


Note that the leader node needs to set the .ag .eld to 1 , so that data from this group will not be aggregated any more.

in Figure 1, when node y receives a packet from x, it forwards the packet towards the BS without any further aggregation and it does not add the count value of x to its own.


We can achieve such scenarios when the input/output size combined with the internal gate size of the circuit makes such logic analysis and reduction intractable in the average case.

the only guarantee that an adversary recovers components when they are originally configured in such "no-win" scenarios (D in Figure 3) is when the circuit is conducive to perfect minimization to begin with (i.e., the semantics of the truth table would clearly reveal component independence or boundaries).


If it is preferred, Naor and Reingold s [8] technique could be used to replace the functions f3,K and f0,K in EK (·) with two pair-wise independent permutations.

let h1(·) and h2(·) be two pair-wise independent permutations on the set of 2n-bit binary strings.


The worm still infects the non-NASR subnets quite rapidly, with a slowdown in the order of 50% caused by the worm failing to infect NASR subnets.

nASR has a milder but still notable impact on non-NASR hosts.


Ken Olthoff wondered whether NSPW's influence on the attendees is more sj~rnlt~Cant than influence on others.

do the NSPW attendees go out and '~prosely-tize?"


In contrast, our work proposes a simple but .exible mechanism for collaborative management of shared data in OSNs.

we introduce an effective con.ict resolution solution, which makes a tradeoff between privacy protection and data sharing considering the privacy concerns frommultiple associated users.


Reasoning about strings and non-strings simultaneously is thus necessary.

we need to deal with a multisorted theory which includes, at least, strings and integers.


First, VM images need high integrity, because they determine the initial states of running virtual machines, including their security states.

the security and integrity of such images are the foundation for the overall security of the cloud.


{0, 1}l for i =1, 2 used in the proposed protocol is secure.

it is easy to compute Hi(m) for given m, however, it is computationally hard to compute pre-image m¯given Hi(¯m).


The collection, storage and processing of data must be in accordance to the principles discussed previously.

the data collection must be restricted to necessary data only, securely stored and the policies of sharing data must be clearly stated to the user (see also Section 6, Privacy Seals).


Thus, our evaluation in this part is focused on the quality of the generated signatures, especially the false positive rate.

we would like to see how much improvement we can get using correlation of message signature with program execution state.


We then reduce the game to the subtree TV1 .

we consider the game G(Y,X |V1)TV1 , with parameters (k, d - 1, P(Y |V1)TV1 , P(X|V1)TV1 ) (see Subsection 6.2).


the They further assumed that two characters that xored to 0 were both equal to space, the most common character.


The detection function of an SVM for an unknown sequence x of events is given by f(x)= (f(x), w) + b =Ie(x) we + b. e.E where f(x) simply returns the orientation of f(x) with respect to the hyperplane.

f(x) > 0 indicates malicious behavior in the sequence x and f(x) = 0 corresponds to benign activity.


An access control mechanism usually relies on one or several access control policies, which are functions associating access queries with decisions.

given a set of queries Q and a set of decisions D, a policy is a function p : Q .


As the number of sessions and permissions increase, the expectation is that the HWDS BitSet SDP performance will degrade due to over.ow handling.

the threshold for over.owing a HWDS is when the number of inserted nodes exceeds the number of sessions times the maximum permission identi.er divided by 64.


Receipt of a text message may be the only way this method is executed.

the .message.SmsReceiver code may never be invoked if the instance never receives a text message.


The attacker in PETRA s threat model can jeopardize the integrity and authenticity of the software update components by executing weak man-in-the-middle attacks on network traffic.

the attacker is assumed to have the necessary expertise and tools to conduct any type of modification and fabrication attack on the network data without being capable of physically compromising the communicating end systems, namely the content distribution server and the update client.


This likelihood information can be used to improve the mapping process of the signature string to the WM objective function, thus increasing the WM strength.

the heuristics can be used to decide if each bit bi.S should be mapped to the variable xi or its complement xi (+ or in the objective function) in order to increase the likelihood that assigning variables according to S would result in a valid solution.


This also means that, upon every variable access, TMI appends information identifying the variable in question to a transaction-speci.c introspection log.

the introspection log will contain information about the creation, reading, and writing of the security sensitive variables.


Suitable access control settings on such nondeterministic components that reside within each machine Mi suf.ce to enforce the policy.

consider the access control setting for M1 depicted in Figure 10.


These new instructions are not intended when the original kernel code is generated.

if these instructions happen to end with a ret instruction, they can be potentially combined to form a gadget as an organizational unit in return-oriented programming  and perform some (malicious) primitive operations, such as a comparison of two register operands or a memory load from a speci.ed location.


Two nodes are joined by an edge if there is a certificate in which the entity of one node certifies (digitally signs) the public-key of the other.

if Alice certifies the public key of Bob then there is an edge from Alice to Bob (in some papers the arrow points the other way).


Those exceptions will be activated only from an integrity level {u}.

if a process has integrity level {u1,u2}or {u1, net}, it does not get any exceptions when loading the setuid root programs.


As we have already noted, this does not mean that tokens should be identical across servers only that there should be considerable overlap in the brute-force computation needed to solve the puzzle for a given channel-number across servers.

it is not desirable for one server to be able to use its shortcut to compute the tokens associated with another server, as this would result in a di.usion of trust across all participating servers rather than in the bastion alone.


We only require that signed objects exist in a collision-free namespace.

the underlying OS prevents the existence of more than one signed object with the same name.


In addition, the Circle pattern does not allow to stay on one line as opposed to a quadrangle.

for the circle patterns this increased the overall entropy estimate.


DETERMINING A PARALLEL SESSION ATTACK ON LOWE S MODIFIED WIDE MOUTHED FROG PROTOCOL This section presents an analysis of Lowe s modi.ed Wide Mouthed Frog protocol using OFMC[3].

a weakness of the protocol is identi.ed that can be exploited in a parallel session attack.


Care is thus required when applying our results to general real-world settings, e.g., large-scale smart grids, where locational prices are important.

propositions 1 to 5 are based on the linearized abstract supply and demand models at a .xed operating point.3 The security analysis in Propositions 2 to 5 is based on the approximate aggregate demand model in Eq.


First and foremost, we would like to know whether interactive computation can be compressed.

whether the interactive information complexity is equal to the communication complexity of any function: Problem 1.


These access rights are de.ned either jointly by the MC and the patient, or directly by the medical authorities.

we note that homomorphic encryption lets the MC compute Pr(X) using encrypted SNPs of patient P. the MC does not access P s SNPs to compute his disease susceptibility.


Now notice that in this architecture the physicians scores sjk cannot be revealed because of the privacy requirements.

suppose that the computational servers post the scores which patients can use to compute necessary recommendations.


identity tokens and their management are important components.


{0,1}m, de.ne µt to be the input distribution µ, conditioned on the .rst m bits of communication equaling t. Our motivation here is two-fold: .rst, examining general distributions allows us to appeal to the geometry of .({0,1}×[k]).

we show that the success of a protocol satis.es certain concavity conditions when viewed as a function s : .


By doing so, we can not only maintain a smooth continued execution of the suspect process after relocation, but ensure its isolation from our monitoring tools.

fromthesuspectprocess perspective, it isstilllogicallyrunninginside theproduction VM.Inthe meantime,asthesuspectprocessphysicallyruns inside the security VM, the monitoring overhead will not be in.icted to the production VM, thus e.ectively localizing monitoring impact within the security VM.


Wurster and Van Oorschot discuss this problem in the context of application developers [23], proposing that developers only be given development choices that lead to a secure program.

developers, OS distributors, and system administrators should be given a small, coherent set of choices that enable them to provide their function in a secure manner.


With respect to the previous experiments on the Banana-shaped data, and on the Malware data, the results here are signi.cantly di.erent.

note how the Random and Random (Best) approaches are totally ine.ective here.


If the attacker is able to guarantee that all the injected faults belong to the selected model, the analysis will conduct to the correct key for sure.

the correct key will remain in the set of candidates with a probability of 1 until the last pair is considered.


Our observation is that both paradigms, though inspired from totally di.erent biological processes, use naive tra.c features as an input to the classi.er.

both paradigms pay no attention to intelligent features that can accurately discriminate malicious and benign network activity.


For example, a resiliency policy in the subcase RCP(s = 0, d = 1)has the form rp(P, 0, 1, t), which asks whether there exists a set of users of size at most t that together have all permissions in P ; while the subcase RCP(t = 8) asks whether there exist several distinct sets of users (d sets) each of whose users together have all permissions in P , even after any set of s users is removed from the state.

rCP( ) is the general case of the problem.


We study the e.ectiveness of address-space randomization and .nd that its utility on 32-bit architectures is limited by the number of bits available for address randomization.

we demonstrate a derandomization attack that will convert any standard bu.er-over.ow exploit into an exploit that works against systems protected by address-space randomization.


Since the encryption and decryption keys are unique in our problem domain, we will adopt the succinct notation [x] to represent an encryption or ciphertext of x. an AH-Enc has the following properties: The encryption function is additive homomorphic: [x1 + x2] = [x1] × [x2] mod N2;  Given a constant c and [x], [c · x] = [x]c mod N2;  The encryption function has semantic security as de.ned in [20], i.e., a set of ciphertexts do not provide additional information about the plaintext to an adversary with polynomial-bounded computing power.

two encryptions of x di.ers with very high probability.


There ¯¯fore, subgraph H1 and H2 are of equal size and satisfy the structural requirements of isomorphism.

there is a bijective mapping from V1 to V2 that preserves the connectivity between ¯¯these nodes.


1 d(Ps(O),Fs(O)) < K~N~ - 1 I P+Q-1I= (1) = ~ (P-=i~---1) recalling that N = PQ is an RSA modulus and ¢ = (P-1)(Q-1) for the second step.

they are statis- tically indistinguishable for the adversary and the theorem follows.


If we track all 100,000 clients, we get the false positive rate around 0.28, which is slightly smaller than the probability 0.35 to detect the right client for a transaction.

for each suggested client the probability that he is the right one is about 55%.


The Consumer Agent interacts dynamically with the Reader Core and Policy Engine.

it logs reading operations that have been performed or denied.


If TRV is con.rmed .rst in the block chain, TRA can never appear in subsequent blocks.

v will not have its BTCs 7Note that our analysis is not restricted to the case where the recipient address is controlled by A and applies to other scenarios, where the recipient is another vendor.


C enforces MAC policies that prevent information .ow to insecure channels, such as removable storage devices.

we do not consider the challenge of securing the application after authentication occurs.


General guidelines on security features to improve user trust in websites include: x Inform the user that he/she is accessing a protected resource to convey the meaning that the session is protected using the secure http protocol (https).

data travelling in the networks are ciphered.


The occluded eye Occeye , makeup mk, and illumination illsd have negative impact and lower the risk of OSNFD.

the occluded eye leads to decrease in the performance of face recognition algorithms, as accurate localization of eyes is important for the alignment process in all major face recognition algorithms [1].


INTRODUCTION An important feature of the Android operating system is that it relies on mature technologies such as the Linux kernel.

android s Dalvik runtime system relies on Linux process creation when launching an application or a service, making the runtime system as the parent process of all user application processes in Android.


Combining together these components will ensure that the response and investigation team members will be able to e.ectively manage the required tasks.

the system model e.ectively integrates the technical incident response and the legal investigation and prosecution process in a multi-site collaborative manner.


We can estimate the e.ect of this .lter on the distribution, to the extent that xi models the likelihood that a new person will be able to correctly orient image i.

the chance that image i will survive the .lter is simply x 10 , so i 10 the resulting distribution would be f'(xi)= xi f(xi).


Backward Traceability: This occursif,given all the internal state of a target tag at time t, the attacker is able to identify target tag interactions that occurred at a time t. <t [15].

knowledge of a tag s current internal state could help identify the tag s past interactions, and the past transcripts of a tag may allow tracking ofthetag owner spastbehaviour[15].


Thus, for the purpose of simulation, we specify a stochastic parameterization of this set of traces.

we articulate distributions from which the components of the workload s initial state (e.g., number of users, number of objects, etc.)


The false positive rates differ dramatically.

the few users with very high false positive rates corre of the threshold T ji along with his measured P (g ji largest b ji such that P (g ji + b ji <T ji )=0.9.


For two of the scripts used in our experiments, we have done so manually via a proxy.

two upgrade annotations were added to Google Analytics and three to Tynt.


The algorithm discussed hereinafter assumes that the absence or abnormal presence of one or more parameters in a query might indicate malicious behavior.

if an argument needed by a server-side program is missing, or if mutually exclusive arguments appear together, then the request is considered anomalous.


Finally, we take Alice s opinions on her contacts into account by adjusting the value of the likelihood score based on the preference tag pti in ci s pro.le.

more speci.cally, when pti is green , we may apply a bonus ß (say ß =0.5)to d(ci,f).we have b(pti)=1+ ß.


PREVIOUS WORKS In the classical RBAC model [25], permissions are independent from the actual object being manipulated.

a user who has the permission to modify a patient record, can do it on every patient record in the system.


Contrary tothe belief, subjacent to these papers, that the non-equivocation restriction on a Byzantine adversary improves the degree of replication from n = 3f +1 to n = 2f + 1, we observe that signatures (or transferable authentication) also play an instrumental role along with the non-equivocation restriction in improving the resiliency bound.

we prove that assuming at most f Byzantine faults in an asynchronous system of n processes, the non-equivocation restriction and transferable-authentication tokens together, but not individually, are su.cient to improve the resiliency bound to n = 2f +1.


ANALYSIS OF INFECTION RATES The instrumentation of Carat intended to be a battery saving app is necessarily lightweight.

we cannot perform detailed analysis of the applications on the device to decide whether it is infected or not.


However, without appropriate security measures, use of a single workstation could magnify the risk of information leakage.

residual information in memory or other internal components of the workstation allocated during a high session may be improperly reallocated to a low session.


One possible explanation of this phenomena against the conclusion in [31] that perturbated precoding is optimal in terms of SINR is that the degrees of freedom in our optimization problem are not full.

unlike the optimization problem of perturbated precoding matrix which can modify any components in the precoding matrix, our optimization problem can only control the second row of precoding matrix, i.e., f21 and f22.


Foreachofthis methods,wevariedthe numberof training patterns, T ,from2to20,andwe tested10differentvaluesforthe threshold (ß ).

since the two considered algorithm DTW-D and DTW-S work in different ways, we also considered for the two of them different set of threshold values.


, aN ) are generated by Gen instead of being randomly sampled by O.

during the setup phase O randomly samples g0 and generates (a1, .


Flow of information via .le objects is simpler than that of pipelike objects.

an object created by a subject receives the label of that subject.


In addition, for each chunk the veri.cation builds an intrachunk CFG and invokes a custom IRMCheck procedure on the CFG.

the veri.cation is parametrized by an IRM s check procedure, which validates that there is suf.cient instrumentation in the chunk according to the IRM s policy.


These standards show thesameprocedures as in cdmaOne.

during registration (invoked by the SSD update procedure, lines b1to b12), the HLR selects a RANDSSD and calculates a new SSD which can be shared with a VLR (lines b1and b2.)


We used testing to construct a permission map that identi.es the permissions required for each method in the Android API.

we modi.ed Android 2.2 s permission veri.cation mechanism to log permission checks as they occur.


Finally, we evaluate the scalability of CoCA by measuring the latency and CPU usage of CoCA with the respect to parallel forensic data transfer requests (Section 6.3).

6.1 Data Acquisition To emulate di.erent and realistic forensic data acquisition scenarios, our .rst set of experiment measures the latency of taking snapshots from the VMs, which run di.erent IaaS cloud services: computational intensive, memory intensive, disk intensive,and networking intensive.the computational intensive VM compute the 1/N!


This may not be surprising as more information provides a better knowledge base for the recommenders.

p.Complete and Profile scaled very well over the amount of available data as they had the largest improvement rates in High over Medium and Low.


Their framework is based on default logic and provides interesting properties such as non-monotonicity of authorizations.

if a set of au- thorization rules is augmented by a new rule, a subject who was previously allowed access to an object may no longer be allowed the same access.


By carefully selecting the state encoding, an NI unit can exhibit desirable degree of random switching variations.

we implement two types of NI unit: 1) FSM with state encoding to achieve adjacent state Hamming Distance variation; 2) Linear Feedback Shift Register (LFSR).


In the protocol, we use various optimizations to ensure that its runtime is as low as possible.

we use varying-length representation in bit decomposition bits and comparison bit-le operations.


A policy-speci.c decryption blackbox is a decryption blackbox that is able to decrypt ciphertexts with some speci.c access policy, say AD.

unlike a key-like decryption blackbox which has an attribute set, for example, SD attached as the alleged decryption capability as the blackbox advertised by the seller, a policy-speci.c decryption blackbox is only known to be able to decrypt ciphertexts with some speci.c policy AD.


Control-.ow graphs are constructed with the help of LLVM.

the LLVM compiler preserves meta-information so that a precise intra-procedural 6This assumption can be discharged by either putting jump tables into code region as in HyperSafe [32] or have read-only data write-protected through page protection.


Even though this migration is necessary for efficient health care service, it opens up a big can of worms with respect to security and privacy issues.

when the doctors and patients access this medical information through the Internet, there is a large room for cyber security attacks.


A would like to know whether she is eligible for the loan while disclosing as little information about her attributes as possible.

a does not want to  disclose the exact values of her DoB or salary level.


It points to the master entry that contains the lexicographically smallest path hash that is greater than the path hash of its own master entry.

master entries form a linked list with all elements sorted by their path hashes in ascending order.


Di.erent from a group signature scheme (for examples, [12], [10] and [3]), the group formation is spontaneous and there is no group manager to revoke the identity of the signer.

under the assumption that each user is already associated with a public key of some standard signature scheme, a user can form a group by simply collecting the public keys of all the group members including his own.


Other processes are run by the database proxy.

dBproxyRu and DBproxyRv containprocesses that receivedatabase recordsfor u and v, respectively; and DBproxySu and DBproxySv contain processes that senddatabase recordsfor u and v, respectively.


BLUETOOTH SECURITY Let us start with a brief review of the strengths and weaknesses of the security mechanisms de.ned in Bluetooth.

we discuss how existing weaknesses can be exploited to attack communicating Bluetooth devices.


She would like to move the coin from A to a new address A ' , such that no one knows that Alice controls A ' .

she wants addresses A and A ' to be unlinkable, despite the public visibility of transactions on the block chain.


The requirements on these cross groups {G ' 1 , ..., G ' } are: (1) each m cross group includes exactly one sensor node from each deployment group, and (2) there are no common sensor nodes between any two different cross groups.

for any iand jwith i j, we have G ' j = i nGj|= 1.


When a smartphone registers with the proxy, it randomly picks up a type with equal probability.

roughly half of the devices are traders, and the other half are tradees.


be an (~,c + 1)-coding scheme that follows the multiplicity paradigm with columns ~" c3 i) ln(~) {Vc}.

then ~ = (iS~WZ log ~ when > K max{(E(V~) log c)/c, clog c} for some constant K. no secure multiplicity code has length e = o( log 5) Proof.


In this paper, we develop a new cryptographic scheme called Ef.cient and Tiny Authentication (ETA), which is especially suitable for resource-constrained devices.

eTA does not require any expensive operation at the signer side and therefore is more computationally ef.cient than traditional signatures.


The worm continues to infect the network, while host computers in the network remain in the susceptible or infectious states.

{TR < TW} is the event that a buffer overflow occurs before the end of the attack, while host computers in the network remain in the susceptible or infectious states.


Whereas functional capabilities of technologies are tested via controlled deployments (e.g., pilot projects of smart grids), security evaluations are often not part of the analysis scope in the running pilots.2 Therefore, we think the paradigm of new technologies as social experiments has added value for cyber security.

when security aspects of the experiments are designed consciously, ethical problems may be avoided, and more data could become available for learning.


We show how an attacker instance can monitor the victim so as to obtain a padding oracle to break XML encryption schemes.

we demonstrate a Bleichenbacher attack [6] against SimpleSAMLphp, an opensource SAML-based authentication application that implements PKCS#1 v1.5 RSA encryption in a manner resistant to these attacks via other vectors (but not via our side-channel attacks).


This has been later generalized to other types of metrics, such as the set di.erence metric [5] and the edit distance metric [6].

the fuzzy vault [5] uses polynomial interpolationinordertoallowauthenticationbasedonthe matching of a su.cient number of features, while the fuzzy extractor [6] is a further generalization which combines the previous constructions with particular objects called random extractors.


for the scheme due to Hancke and Kuhn in Section 3.1.

the response strings T 0 and T 1 are now related by means of the secret key sk * .


We chose a hash-tree [27] based approach, which has also been demonstrated in the Trusted Database System [25].

data blocks in a .le container are nodes in a self-protecting hash tree, with a layout as illustrated in Figure 3.


and an input identi.er t. Input identi.ers, in isolation, are used to label the variable inputs of a function f, whereas the combination of both, i.e., the full multi-label L = (., t ), is used to uniquely identify a speci.c data item.

binding a value m with multilabel (., t ) means that m can be assigned to those input variables with input identi.er t. The pair (., t ) is necessary to uniquely identify m. While one can still not re-use a pair (., t )for authentication purposes, one can re-use the input identi.er t, instead.


A migrateable instance is an instance that can either be: (i) migrated to the new policy; (ii) migrated to a temporary ad-hoc policy; or (iii) left running according to the old policy without causing violations.

these are instances we can somehow deal with without revoking privileges or ignoring new restrictions introduced by the new policy.


We now shift focus to converting the model speci.cations into a suitable implementation design for the prototype.

we are interested in the document data and the document metadata, two components forming the document model.


Second, the usability objective is that it neither forces the users to understand the complex permission system, nor requires much signi.cant (if any) involvement of users in managing/using it.

it should be as transparent as possible to the users.


Much of the focus of identity 2.0 (as promoted by organisations such as sxip12) is on the multiplicity of things that we say about ourselves, and the things that others say about us.

identity 2.0 begins with a realization that the usefulness of online identity depends on context, and it must be responsive to the natures of the diverse relationships we have with those we transact w13 It seems to be increasingly accepted that people live with multiple identities.


When a system call needs to be .ltered, the kernel executes all the programs along this reverse linked list.

a parent s program is inherited by the child processes.


RBDM0 allows user-to-user delegation based on roles [Bar00a, Bar00b].

a user (delegator) assigned to a role (delegator role) delegates his role membership to another user (delegatee) assigned to another role (delegatee role).


ProtectMe architecture is composed by a number of components, that follows to a certain extent XACML architecture for access control, extending it with usage control directives proposed by [4].

protectMe is composed by: Policy Enforcement Point (PEP), that exposed methods to access protected resources; Policy Decision Point (PDP), that is responsible for evaluating requests received by PEP, interacting with other modules like SPP and PIP; SP management Point (SPP), that mostly handles resource-policy associations, as well as SP retrieval: in fact, it parses SPs  Figure 2: ProtectMe Policy Rendering and stores them in the Android SQLite DB, to optimize performances; Policy Information Point (PIP), responsible for gathering data from mobile device sensors; and a fa¸cade, that exposes the publicly available functionalities, in the form of an Android service interface.


Generally, attackers may perform the following operations by abusing Address Book Matching: Attackers may obtain users pro.les and the associated phone numbers.

a link between real identity and virtual account has been established.


2.3 Secure Boot Another application for inherent PUFs is to use it as an identi.er for a given device, which is used to implement a secure boot process tying software to a speci.c physical instantiation of a Cortex-A processor.

we derive a .ngerprint from the intrinsic SRAM of an System-on-a-Chip (SoC) platform to identify the device.


Recent works on ORAM [21, 24, 25, 30, 31] have shown that even the fastest known constructions incur a large bandwidth overhead in practice.

under typical parametrizations, and with O(1) amount of client storage, known ORAM constructions require 400+ blocks be transferred between a client and a server for a single data access.


We refer to this requirement as in-band key distribution.

we do not rely on any other external key distribution infrastructure.


This paper provides a description of the Capability Based Access Control (CapBAC) system being developed in the EU FP7 IoT@Work project (http://iot-at-work.eu) to address specific issues in an IoT world.

the IoT@Work project focuses on harnessing IoT technologies in industrial and automation environments.


Note that analysis systems usually treat binaries scheduled for analysis as a mathematical set consisting of unique .les.

to save analysis time, one avoids analyzing the same .le multiple times.


Since all malware infections we have observed are triggered by users actively downloading malware from the online marketplace, detection and removal of malware at the online marketplacehasproved tobeane.ectiveway ofpreventing fraud activities.

our analysis suggests that the online marketplace should come up with more advanced vetting process for the apps, especially if it contains code segment involved with voice calls or SMS messages.


We insist that any su.x Ri+1,...,Rt of the original sequence looks uniformly random, even when given the pre.x R ' 1,...,R i ' in the related sequence.

the adversary cannot modify the seed and use the (incorrectly) extracted blocks to look ahead into the the original sequence of blocks.


Of particular interest are the rules that de.ne how high integrity data is processed securely, where: (1) high integrity data (CDIs) must satisfy integrity veri.cation procedures (IVPs) (Clark-Wilson rule C1); (2) only approved programs called transformation procedures (TPs) may modify high integrity data (C2, E1); and (3) TPs may only receive low integrity data (UDIs) if that data is upgraded or discarded (C5).

tPs protect data integrity, but they require IVPs to validate that the data an application depends upon is high integrity and TPs must be capable of mediating low integrity inputs to upgrade or discard such data.


In either case, we can represent these constraints as the restrictions on the width and depth of the creation tree, respectively.

we .rst introduce the following functions: lim cre wi : Capi -N;  lim cre di : Capi -N.  Then the constraints are represented by the following conditions for any c .


Both com plexities, however, aredependenton the size of theblacklist.

the time it takes for both a user and a SP to execute the authentication protocol, as well as communi cation overhead for the same protocol, grow linearly with the current size of the SP s blacklist.


Since the contact information includes a public key, only that public key is used to subsequently establish secure communication.

all cryptographic values created during the exchange (Figure 4) are erased after the exchange the sole purpose of their brief existence is to protect a single exchange.


The entropy in that name depends on the size of the community.

if there were only two people in the world, the only name we would need would be you for zero bits of entropy.


For our attack to be successful, we only have to overcome a single security check located inside the in-app billing-enabled victim app.

this check is the signature verification of the purchase data returned to the application by the Android Play Store.


To be conservative, we use the current draw with radio on in our computation.


This mechanism is independent of the underlying protection model and can guarantee that trust assumptions are always preserved by any proper implementation of the speci.cation.

we describe how to generate authorization guards and show how they preserve the authorization safety property in all transitions that can modify the state of the access control implementations.


In addition to patching individual VM images, Nüwa also leverages VM image manipulation technologies to further improve scalability.

nüwa uses features of the Mirage image library [24] to enable scalable patching of a large number of VM images in batch.


This function can be used to obtain the user s attributes in data encryption.

the result of ..................(..)can be used to establish access policy through simple logical relationship.


However, it has been proved that Greedy-Search algorithm is an Hn-approximation algorithm for the MSC problem.


Hence, we aimed to adopt already existing techniques such as shadow stack [15, 59, 26] for return addresses, and the concept of binary instrumentation as used in taint tracking [47, 17] or return address protection [29, 16, 37].

our 2Moreover, it has been used in [61] for a checksum-aware fuzzing tool and in [17] as dynamic taint analysis system.


5.1.2 Acyclic & Bounded Query-width Queries There has been extensive work on relating the structure of conjunctive queries and the hardness of query containment.

chekuri and Rajaram [7] relate the hardness of query containment to the cyclicity of the query graph.


The results for di.erent binarization thresholds are reported.

it can be noticed that in all the cases the Permission Similarity is always greater than 90%(Figure 3(a)).


In Figure 9, for the most part the posterior probabilities for room 301 is less than 03when the correct position is not equal to that room.

by setting the threshold to 03or greater, the presence inference engine gives a good precision.


In the context of this analysis, a guess is therefore a guess against each target in the target set.

if we state that we are applying 500 guesses , we mean 500 guesses per target.


Therefore, our framework develops a data preprocessing strategy to cope with CSI samples to mitigate the e.ects caused by such temporal bias.

we observe a shift on the amplitude of a speci.c subcarrier due to the interference presented at either transmitter or receiver.


We note that in this case the adversary s vulnerability period grows linearly with the time elapsed after the last exposure.

the longer the adversary waits to use the stolen secret, the higher are her chances of being caught.


Our solution is conceptually simple and ef.cient, which makes it suitable for practice.

it consists of the following two stages.


Memory-based .ngerprinting Recently a couple of techniques were proposed to utilize the memory data for OS .ngerprinting, but none of them can simultaneously achieve all of the three design goals: ef.ciency, accuracy, and robustness.


Then, formula (8) states that predicate ipspoofed(sensor, srcI P, srcEth)is trueif and only if sensor can sni.

packets coming from physical address srcEth (which is connected to link l and is associated with IP address srcEthI P ), and there is no path p between the host srcI P H ost of IP address srcI P and node srcEthI P such that p does not include link l.ipspoofed(sensor, srcI P, srcEth) is true when a packet with source ethernet address srcEth and source IP address srcI P is spoofed, and a sensor on node sensor can detect it.


It should be noted that the e.ectiveness in the reduction of false positives is highly dependent on the nature of each application, as well as on the level of the execution s source coverage.

the more integer operations occur throughout the execution, the greater the expected numberoffalsepositives.


fraction of a with probability 1 - d. To see this, observe that Q can be used to answer queries a · q for any arbitrary  v q to within o( m) additive error.

to answer (1) (r) queries a · q1,..., a · qr, run Q(X, S),..., Q(X, S) in tt parallel, where St (i) is a stream with state qi.


The main idea of SynchroTrap is to use clustering analysis [26] to detect the loosely synchronized actions from malicious accounts at scale.

it measures pairwise user behavior similarity and then uses a hierarchical clustering algorithm [26] to group users with similar behavior over an extended period of time together.


We use c to denote an unspeci.ed constant.

whenever c appears we can replace it with some universal constant.


The advantages of our approach are: (1) the model is applicable to a wider variety of contexts, and (2) the security requirements are expressed in a clearer way, with bene.ts for the security administrator and the reasoning system.

we provide a complete technique for the identi.cation of query compliance with authorizations and formally demonstrate the correct behavior of an e.cient composition of authorizations, whereas in [16] no algorithm is provided for the evaluation of view composition, relying instead on a potentially expensive application of a few heuristics by the query optimizer.


fectiveness as being with respect to utilities whose typicality rank is bounded above by some value r. If, whenever someone commits theft, there is always some non-zero probability that he will be tried, convicted, and sentenced, then because the penalty in question quali.es as punishment this satis.es our working de.nition of accountability.

the thief is accountable for his theft (although he might escape punishment in a particular case).


Note that we always has |Ur| = |Ua| at the end of a simulation instance.

if a recommender does not return any suggestion, the user will have to manually enter |Ua| recipients for f. The simulation algorithm is given in Figure 3.


B1 as her next message instead of terminating the negotiation.

though theoretically there is no hope to establish trust, Alice may still continue the negotiation until she cannot make any safe disclosures.


In our work, we assumed that the certificate graphs in self- organized systems exhibit certain properties.

we assumed that the certificate graphs that might appear in self-organized systems exhibit the small-world phenomenon.


Namely, data in databases are also mapped to rings, such that a request in subsession t can only access the data in rings t and above.

we label tables of databases with rings depending on the level of protection required by web applications.


On the other side of the spectrum (op-This ratio characterizes how geographically distributed the posite of too generic graphs) are graphs that are too small.

various starting points (referrers) that lead to a certain web these graphs contain too few chains to extract mean-page are.


We require that once a tag is read and randomized by an honest reader, it cannot be traced by the adversary.

if between two reads of the tag by an adversary, the tag is read and randomized by an honest reader/randomizer, then the adversary is not able to distinguish whether or not it reads the same tag.


If A is least-restrictive, then subjects are not independent.

the actions of a subject can constrain the prospective actions of other subjects.


The plane used to embed the data is chosen based on the integer value of each 8-bit message block.

if the integer value of the 8-bit message block is between 0 and 85, the embedding of these 8-bits under consideration, takes place in the R plane.


O)k , k denoting the maximum number of parameters in a model s command set.

the state transition function d of an HRU model is de.ned by a .nite set of partial de.nitions where each de.nition speci.es the parameters, conditions, and effect of a single command in C. In the example above, the condition read_right .


IP address is by monitoring all IP addresses in netblock containing one ore more known malicious IP addresses, and building network behavioral pro.les of all these IP addresses over time.

given a malicious IP address, we .rst determine using public registry information, the smallest registered netblock that contains that IP address.


As shown in Figure 5 (a), as the number of nodes increases, the overhead of SAP v3 is much smaller than that of SAP v1.

as shown in Figure 5 (b), the overhead of SAP v3 is linearly proportional to the number of groups.


If the browser process is forced to access a memory address that does not contain shellcode, it is likely to crash, causing the attack to fail.

reliable exploitation requires that the attacker have precise control over the browser s memory layout.


Since the mobility trace does not have an explicit graph structure, supposing the social graph is the ground truth, we apply the technique in [27] on the mobility trace to construct four graphs with di.erent recalls and precisions, denoted by M1, M 2, M 3, and M4,  tp tp respectively (recall = and precision = , where tp+fn tp+fp tp = true positive, fp = false positive, and fn = false negative).

the recall and precision of M1 are 0.6 and 0.865, of M2 are 0.72 and 0.83, of M3 are 0.75 and 0.78, and of M4 are 0.8 and 0.72, respectively.


The counter should ideally be tamper-resistant, but must at least be tamper-evident.

it must be infeasible for an adversary to directly or indirectly cause the counter to behave incorrectly without at least being detected.


However, we do not assume that each SP trusts all possible SR domains explicitly.

we do not require the web of trust between domains of SPs and SRs; instead, xDAuth leverages the DS as a proxy of trust.


2.2 The Ideal System for Group Key Exchange Our ideal system Sysidealgkefor group key exchange models how nservers repeatedly establish a session key.

we say aserver istarts a session with tag IDwhen an input (start,ID) occurs at ini(IDis an arbitrary bit string and represents a unique identi.er for the session).


The distinction between space and place has a long tradition in sociology and over the years has been applied in fields as diverse as, for example, cinematic theory [34] and Computer Supported Cooperative Work (CSCW) [35, 36].

here we refer to the notion of place as defined by Gieryn [37].


Several properties of the hypervisor code allowed the usage of weakest preconditions to be e.ective.

the loops have always a structured control .ow, with a conditional instruction that represents both the enter and exit point of the loop.


In this paper, we mainly investigate the impact of user guidelines on creating click-draw based graphical passwords.

we conducted two experiments with 60 participants as follows: (1) Recording created graphical passwords from 20 participants without user guidelines, and then recording created graphical passwords from the same 20 participants by providing them with user guidelines; (2) For the remaining 40 participants, we equally divided them into two groups.


Therefore, during design time, we specify t s people link in such a way that the user repository returns all users who are assigned to a role in Rt.

the user repository keeps track of the user-assignment relation UA and the work.ow de.nition speci.es the permission-assignment relation PA. Implicitly, we assume a one-to-one relation between permissions and tasks.


This paper does not conclusively answer these questions, but we develop a measurement methodology that is a .rst step in this direction.

we focus on how to identify and measure the diversity among remote code injection exploits used to compromise Internet hosts.


Of course, indistinguishability is unachievable against an attacker who does know tB : the attacker can simply verify the signature.

we encode R as t both for transmission and for input to H. We could safely switch to a di.erent encoding for input to H. we could use the same encoding used in EdDSA.


3.4 Discussion Each strategyfordirectingqueriesinourresolution mechanism is capable of resolving a majority of policy miscon.gurations.

the UPPA strategy, when allowed to consult two users, is able to resolve almost 95% of such miscon.gurations.


Algorithms have also been developed for the segmentation of .lament data in serial microscopy volumes.

the algorithm developed by Al-Kofahi et al.


Here, Mallory intercepts a set of l queries Q = (Q1, ··· , Ql) and has access to KQ and M de.ned earlier.

let us assume that Mallory already knows the corresponding keywords for each of the queries in the set S .Q.S = {y|.x (x, y).


As a matter of fact, this scheme is vulnerable to the pixel count attack we discovered in [15].

by counting the number of foreground pixels, we could recognise most of the characters.


We show how every attribute predicate can be rewritten in terms of building blocks.

any attribute predicate witharbitrarylogical nesting and negations canbe trans formed todisjunctive normalform(DNF),i.e., ij lij , where lij is an atomic expression(AtomicExp in Table 2) with no further logical structure.


According to the above analysis, we can see that no appropriate .elds can act as signatures in the socket data structure.

it is impossible to generate an e.ective signature from a single data structure (intra-structure) for scanning socket objects.


There is a large body of work on improving the security of OSes and mobile apps.

researchers have paid considerable attention to protecting personal user data (e.g., address book, user photos, password information, GPS location) and preventing its unauthorized access and leakage by proposing novel techniques, such as new access control mechanisms [33] and information .ow analysis [20].


Based on this model, we showed that very strong privacy notions are unachievable for certain classes of reputation function.

if a reputation function is non-discriminatory (i.e.


Considered the effect of the length of the trust path, we set a variable of distance effect.

the recommendations of peers from near distance have more important than those far off in the trust path.


as this paper is being written, we are currently using the NRL Protocol Analyzer to verify that GDOIsatis.es these the intruder should not learn a key KG for G unless some group key has previously been lost, a dishonest requirements.


A hybrid hierarchy in which these different hierarchy types coexist can capture fine-grained inheritance semantics [Jos05 Jos02a, Jos03, San98].

when various separation of duty (SoD) as well as user-centric and permission centric cardinality constraints need to be applied on roles in a hierarchy, A-hierarchy can be used [San98, Jos02a].


The result shows that even on this relatively low performance ARM processor, ARMlock can perform 903, 342 inter-module calls every second.

each inter-module call takes about 1.1µs.


The servers will then be able to update the scores for all physicians and all conditions using the data received from the patient without the ability to know which particular value has been modi.ed.

this can be accomplished as follows: the computational servers maintain (protected) sums rjk and weights wjk for each physician j and condition k.When anew rating rijk of weight wijk is submitted, the sum of ratings is updated as rjk + rijk and the weight is updated as wjk + wijk.When rijk and wijk are both 0, nothing is modi.ed.


Prior work on improving the security con.guration in a network of machines has required substantial manual e.ort by the IT administrator [2, 52, 48, 38, 35].

these systems may repeatedly propose con.guration changes that are not implementable, or they may require the IT administrator to specify particular high-value machines that must be defended.


Cryptography hides patterns in user data but does not evade censorship if the censor can recognize patterns in the cryptography itself.

elliptic-curve cryptography often transmits points on known elliptic curves, and those points are easily distinguishable from uniform random strings of bits.


Limitations The rule does not work if both tasks write on the shared state, because they can still in.uence each other via these components.

the indirect permissions of both components will not have been decreased.


We stress that a naive encryption is not enough to completely realize the above rationale.


After dividing the reference and anonymized graphs into communities, these communities can be mapped .rst, and then users can be matched and re-identi.ed for each corresponding community.

our approach can employ an existing communityblind mapping algorithm such as the NS algorithm for communityand node-level mapping.


To that end, we are currently working on an implementation of such an assessment tool.

we use this prototype to experiment with automatic processing of user input, visualization with automatically generated graphs, and automated computation of the quantitative results.


In this context, a user might be well advised either to (a) choose a very strong password that the adversary will never crack, or (b) choose a password of the sort that the honeyword generator might generate.

don t pick a password that has obvious structure to a human of a sort that an automatic generator might not use.


The next (sequential) composition property allows to simplify cryptographic security proofs and omit unnecessary details.

let .g|f denote a sequential protocol for computing functionality g, where parties can access a trusted third party TTP that computes functionality f.parties can send their arguments to the incorruptible TTP that privately replies with the answers f1 and f2.Now, let .f|g ..f denote the protocol, where parties execute .g|f but instead of TTP use .f to compute f. Then the following sequential composition theorem [5, p. 637] holds.


Fernandez andHawkins[6] suggested an early approach todetermine role rights from use cases.

they propose to extend the textual description of use cases in order to de.ne security requirements for use cases.


Else Return .i  The above procedure computes an e.ective strategy S* with respect to A and Csuch that there is no other e.ective strategy S such that S >S*.

the above procedure produces a most preferred, e.ective strategy for the attack graph A with respect to the preferences C.  5.


If the user wants to provide user of the BlackBerry to signal duress by using a modified is constructed by .. version of her correct password.

and moving its first character to the end.


Figure 2(b) shows the number of scheduled tasks for each second during the session.

the session included a Web browser launch followed by an Of.ce document editor application spawn.


Consequently, one has to remember a huge amount of them.

when talking about authentication, not only security and privacy aspects have to be considered, but also the question of complexity.


The relation between > and > is many-to-many association.

a domain can consist of zero or more systems.


Each additional aggregation line adds another 30 µs to the overall execution time.

merging m lines in the transmissionbu.er with an n-linelocal synopsistakesapproximately nm · 30 µs.


2.1 Problem Statement Given a memory snapshot of a VM running in the cloud, we aim to precisely determine the OS version.

we have three design goals: precision, ef.ciency, and robustness.