A vulnerability was found in Axiomatic Bento4. It has been declared as critical. This vulnerability affects the function GetOffset of the file Ap4Sample.h of the component mp42hls. The manipulation leads to use after free. The attack can be initiated remotely. The exploit has been disclosed to the public and may be used. VDB-212002 is the identifier assigned to this vulnerability.
Hi, there.

There is an heap overflow in mp42hls, GetOffset, Ap4Sample.h:99, in the newest commit 5e7bb34a08272c49242196eba1cefab8af55f381. This seems to be an incomplete fix of issue #461.


Here is the reproducing command:
~~~~
./mp42hls poc 
~~~~

POC:
[mp42hls_cuaf_Ap4Sample99.zip](https://github.com/axiomatic-systems/Bento4/files/9817606/mp42hls_cuaf_Ap4Sample99.zip)
(unzip first)

Here is the reproduce trace reported by ASAN:
~~~~
==2007234==ERROR: AddressSanitizer: heap-use-after-free on address 0x604000005dd8 at pc 0x0000005852ab bp 0x7ffc127b7960 sp 0x7ffc127b7958
 READ of size 8 at 0x604000005dd8 thread T0
     #0 0x5852aa in AP4_Sample::GetOffset() const  /benchmark/Bento4/Source/C++/Core/Ap4Sample.h:99:48
     #1 0x5852aa in AP4_LinearReader::Advance(bool)  /benchmark/Bento4/Source/C++/Core/Ap4LinearReader.cpp:434:54
     #2 0x585ab1 in AP4_LinearReader::ReadNextSample(unsigned int, AP4_Sample&, AP4_DataBuffer&)  /benchmark/Bento4/Source/C++/Core/Ap4LinearReader.cpp:530:29
     #3 0x509a31 in ReadSample(SampleReader&, AP4_Track&, AP4_Sample&, AP4_DataBuffer&, double&, double&, bool&)  /benchmark/Bento4/Source/C++/Apps/Mp42Hls/Mp42Hls.cpp:1004:32
     #4 0x509a31 in WriteSamples(AP4_Mpeg2TsWriter*, PackedAudioWriter*, AP4_Track*, SampleReader*, AP4_Mpeg2TsWriter::SampleStream*, AP4_Track*, SampleReader*, AP4_Mpeg2TsWriter::SampleStream*, unsigned int, unsigned char)  /benchmark/Bento4/Source/C++/Apps/Mp42Hls/Mp42Hls.cpp:1289:22
     #5 0x509a31 in main  /benchmark/Bento4/Source/C++/Apps/Mp42Hls/Mp42Hls.cpp:2188:14
     #6 0x7f33bacb6082 in __libc_start_main /build/glibc-SzIz7B/glibc-2.31/csu/../csu/libc-start.c:308:16
     #7 0x41d8ed in _start ( /benchmark/Bento4/build-a/mp42hls+0x41d8ed)
 
 0x604000005dd8 is located 8 bytes inside of 48-byte region [0x604000005dd0,0x604000005e00)
 freed by thread T0 here:
     #0 0x4f88b7 in operator delete(void*)  /dependence/llvm11/llvm-11.0.0.src/projects/compiler-rt/lib/asan/asan_new_delete.cpp:160:3
     #1 0x584f07 in AP4_LinearReader::SampleBuffer::~SampleBuffer()  /benchmark/Bento4/Source/C++/Core/Ap4LinearReader.h:104:26
     #2 0x584f07 in AP4_LinearReader::Advance(bool)  /benchmark/Bento4/Source/C++/Core/Ap4LinearReader.cpp:462:17
 
 previously allocated by thread T0 here:
     #0 0x4f7eb7 in operator new(unsigned long)  /dependence/llvm11/llvm-11.0.0.src/projects/compiler-rt/lib/asan/asan_new_delete.cpp:99:3
     #1 0x584892 in AP4_LinearReader::Advance(bool)  /benchmark/Bento4/Source/C++/Core/Ap4LinearReader.cpp:422:41
 
 SUMMARY: AddressSanitizer: heap-use-after-free  /benchmark/Bento4/Source/C++/Core/Ap4Sample.h:99:48 in AP4_Sample::GetOffset() const
 Shadow bytes around the buggy address:
   0x0c087fff8b60: fa fa fd fd fd fd fd fa fa fa fd fd fd fd fd fd
   0x0c087fff8b70: fa fa fd fd fd fd fd fa fa fa fd fd fd fd fd fd
   0x0c087fff8b80: fa fa fd fd fd fd fd fa fa fa fd fd fd fd fd fd
   0x0c087fff8b90: fa fa fd fd fd fd fd fa fa fa fd fd fd fd fd fd
   0x0c087fff8ba0: fa fa fd fd fd fd fd fa fa fa fd fd fd fd fd fd
 =>0x0c087fff8bb0: fa fa fd fd fd fd fd fa fa fa fd[fd]fd fd fd fd
   0x0c087fff8bc0: fa fa fd fd fd fd fd fa fa fa fa fa fa fa fa fa
   0x0c087fff8bd0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
   0x0c087fff8be0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
   0x0c087fff8bf0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
   0x0c087fff8c00: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
 Shadow byte legend (one shadow byte represents 8 application bytes):
   Addressable:           00
   Partially addressable: 01 02 03 04 05 06 07 
   Heap left redzone:       fa
   Freed heap region:       fd
   Stack left redzone:      f1
   Stack mid redzone:       f2
   Stack right redzone:     f3
   Stack after return:      f5
   Stack use after scope:   f8
   Global redzone:          f9
   Global init order:       f6
   Poisoned by user:        f7
   Container overflow:      fc
   Array cookie:            ac
   Intra object redzone:    bb
   ASan internal:           fe
   Left alloca redzone:     ca
   Right alloca redzone:    cb
   Shadow gap:              cc
 ==2007234==ABORTING

~~~~

Concurrent heap use after free in mp42hls, GetOffset, Ap4Sample.h:99
This is a GitHub Issue
repo:Bento4
owner:axiomatic-systems
Title : Concurrent heap use after free in mp42hls, GetOffset, Ap4Sample.h:99
Issue date:

--- start body ---
Hi, there.

There is an heap overflow in mp42hls, GetOffset, Ap4Sample.h:99, in the newest commit 5e7bb34a08272c49242196eba1cefab8af55f381. This seems to be an incomplete fix of issue #461.


Here is the reproducing command:
~~~~
./mp42hls poc 
~~~~

POC:
[mp42hls_cuaf_Ap4Sample99.zip](https://github.com/axiomatic-systems/Bento4/files/9817606/mp42hls_cuaf_Ap4Sample99.zip)
(unzip first)

Here is the reproduce trace reported by ASAN:
~~~~
==2007234==ERROR: AddressSanitizer: heap-use-after-free on address 0x604000005dd8 at pc 0x0000005852ab bp 0x7ffc127b7960 sp 0x7ffc127b7958
 READ of size 8 at 0x604000005dd8 thread T0
     #0 0x5852aa in AP4_Sample::GetOffset() const  /benchmark/Bento4/Source/C++/Core/Ap4Sample.h:99:48
     #1 0x5852aa in AP4_LinearReader::Advance(bool)  /benchmark/Bento4/Source/C++/Core/Ap4LinearReader.cpp:434:54
     #2 0x585ab1 in AP4_LinearReader::ReadNextSample(unsigned int, AP4_Sample&, AP4_DataBuffer&)  /benchmark/Bento4/Source/C++/Core/Ap4LinearReader.cpp:530:29
     #3 0x509a31 in ReadSample(SampleReader&, AP4_Track&, AP4_Sample&, AP4_DataBuffer&, double&, double&, bool&)  /benchmark/Bento4/Source/C++/Apps/Mp42Hls/Mp42Hls.cpp:1004:32
     #4 0x509a31 in WriteSamples(AP4_Mpeg2TsWriter*, PackedAudioWriter*, AP4_Track*, SampleReader*, AP4_Mpeg2TsWriter::SampleStream*, AP4_Track*, SampleReader*, AP4_Mpeg2TsWriter::SampleStream*, unsigned int, unsigned char)  /benchmark/Bento4/Source/C++/Apps/Mp42Hls/Mp42Hls.cpp:1289:22
     #5 0x509a31 in main  /benchmark/Bento4/Source/C++/Apps/Mp42Hls/Mp42Hls.cpp:2188:14
     #6 0x7f33bacb6082 in __libc_start_main /build/glibc-SzIz7B/glibc-2.31/csu/../csu/libc-start.c:308:16
     #7 0x41d8ed in _start ( /benchmark/Bento4/build-a/mp42hls+0x41d8ed)
 
 0x604000005dd8 is located 8 bytes inside of 48-byte region [0x604000005dd0,0x604000005e00)
 freed by thread T0 here:
     #0 0x4f88b7 in operator delete(void*)  /dependence/llvm11/llvm-11.0.0.src/projects/compiler-rt/lib/asan/asan_new_delete.cpp:160:3
     #1 0x584f07 in AP4_LinearReader::SampleBuffer::~SampleBuffer()  /benchmark/Bento4/Source/C++/Core/Ap4LinearReader.h:104:26
     #2 0x584f07 in AP4_LinearReader::Advance(bool)  /benchmark/Bento4/Source/C++/Core/Ap4LinearReader.cpp:462:17
 
 previously allocated by thread T0 here:
     #0 0x4f7eb7 in operator new(unsigned long)  /dependence/llvm11/llvm-11.0.0.src/projects/compiler-rt/lib/asan/asan_new_delete.cpp:99:3
     #1 0x584892 in AP4_LinearReader::Advance(bool)  /benchmark/Bento4/Source/C++/Core/Ap4LinearReader.cpp:422:41
 
 SUMMARY: AddressSanitizer: heap-use-after-free  /benchmark/Bento4/Source/C++/Core/Ap4Sample.h:99:48 in AP4_Sample::GetOffset() const
 Shadow bytes around the buggy address:
   0x0c087fff8b60: fa fa fd fd fd fd fd fa fa fa fd fd fd fd fd fd
   0x0c087fff8b70: fa fa fd fd fd fd fd fa fa fa fd fd fd fd fd fd
   0x0c087fff8b80: fa fa fd fd fd fd fd fa fa fa fd fd fd fd fd fd
   0x0c087fff8b90: fa fa fd fd fd fd fd fa fa fa fd fd fd fd fd fd
   0x0c087fff8ba0: fa fa fd fd fd fd fd fa fa fa fd fd fd fd fd fd
 =>0x0c087fff8bb0: fa fa fd fd fd fd fd fa fa fa fd[fd]fd fd fd fd
   0x0c087fff8bc0: fa fa fd fd fd fd fd fa fa fa fa fa fa fa fa fa
   0x0c087fff8bd0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
   0x0c087fff8be0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
   0x0c087fff8bf0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
   0x0c087fff8c00: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
 Shadow byte legend (one shadow byte represents 8 application bytes):
   Addressable:           00
   Partially addressable: 01 02 03 04 05 06 07 
   Heap left redzone:       fa
   Freed heap region:       fd
   Stack left redzone:      f1
   Stack mid redzone:       f2
   Stack right redzone:     f3
   Stack after return:      f5
   Stack use after scope:   f8
   Global redzone:          f9
   Global init order:       f6
   Poisoned by user:        f7
   Container overflow:      fc
   Array cookie:            ac
   Intra object redzone:    bb
   ASan internal:           fe
   Left alloca redzone:     ca
   Right alloca redzone:    cb
   Shadow gap:              cc
 ==2007234==ABORTING

~~~~

--- end body ---

A heap overflow vulnerability in the mp42hls component of Bento4 allows attackers to exploit a use-after-free condition in the GetOffset function of Ap4Sample.h. This can lead to potential arbitrary code execution or application crashes when processing specially crafted input files.