bento4: stack-based buffer underflow in AP4_VisualSampleEntry::ReadFields (Ap4SampleEntry.cpp)

Description:
bento4 is a fast, modern, open source C++ toolkit for all your MP4 and MPEG DASH media format needs.

The complete ASan output of the issue:

# mp42aac $FILE out.aac
==4435==ERROR: AddressSanitizer: stack-buffer-underflow on address 0x7fe62b800e86 at pc 0x00000057b5a3 bp 0x7ffea98c1b10 sp 0x7ffea98c1b08                                                                        
WRITE of size 1 at 0x7fe62b800e86 thread T0                                                                                                                                                                       
    #0 0x57b5a2 in AP4_VisualSampleEntry::ReadFields(AP4_ByteStream&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4SampleEntry.cpp:780:40                                                                             
    #1 0x575726 in AP4_SampleEntry::Read(AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4SampleEntry.cpp:108:5                                                                        
    #2 0x57d624 in AP4_VisualSampleEntry::AP4_VisualSampleEntry(unsigned int, unsigned int, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4SampleEntry.cpp:742:5                     
    #3 0x57d624 in AP4_AvcSampleEntry::AP4_AvcSampleEntry(unsigned int, unsigned int, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4SampleEntry.cpp:994                             
    #4 0x5cbf58 in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned int, unsigned int, unsigned long long, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:305:24             
    #5 0x5c7fbd in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned long long&, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:220:14                                        
    #6 0x586a2c in AP4_StsdAtom::AP4_StsdAtom(unsigned int, unsigned char, unsigned int, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4StsdAtom.cpp:100:13
    #7 0x58566f in AP4_StsdAtom::Create(unsigned int, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4StsdAtom.cpp:56:16
    #8 0x5ca71c in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned int, unsigned int, unsigned long long, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:422:20
    #9 0x5c7fbd in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned long long&, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:220:14
    #10 0x60c29f in AP4_ContainerAtom::ReadChildren(AP4_AtomFactory&, AP4_ByteStream&, unsigned long long) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:193:12
    #11 0x60b1d2 in AP4_ContainerAtom::AP4_ContainerAtom(unsigned int, unsigned long long, bool, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:138:5
    #12 0x60b1d2 in AP4_ContainerAtom::Create(unsigned int, unsigned long long, bool, bool, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:87
    #13 0x5ca44c in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned int, unsigned int, unsigned long long, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:751:20
    #14 0x5c7fbd in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned long long&, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:220:14
    #15 0x60c561 in AP4_ContainerAtom::ReadChildren(AP4_AtomFactory&, AP4_ByteStream&, unsigned long long) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:193:12
    #16 0x60b1d2 in AP4_ContainerAtom::AP4_ContainerAtom(unsigned int, unsigned long long, bool, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:138:5
    #17 0x60b1d2 in AP4_ContainerAtom::Create(unsigned int, unsigned long long, bool, bool, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:87
    #18 0x5ca44c in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned int, unsigned int, unsigned long long, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:751:20
    #19 0x5c7fbd in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned long long&, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:220:14
    #20 0x60c561 in AP4_ContainerAtom::ReadChildren(AP4_AtomFactory&, AP4_ByteStream&, unsigned long long) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:193:12
    #21 0x60b1d2 in AP4_ContainerAtom::AP4_ContainerAtom(unsigned int, unsigned long long, bool, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:138:5
    #22 0x60b1d2 in AP4_ContainerAtom::Create(unsigned int, unsigned long long, bool, bool, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:87
    #23 0x5ca44c in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned int, unsigned int, unsigned long long, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:751:20
    #24 0x5c7fbd in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned long long&, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:220:14
    #25 0x60c561 in AP4_ContainerAtom::ReadChildren(AP4_AtomFactory&, AP4_ByteStream&, unsigned long long) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:193:12
    #26 0x60c099 in AP4_ContainerAtom::AP4_ContainerAtom(unsigned int, unsigned long long, bool, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:138:5
    #27 0x58e6ed in AP4_TrakAtom::AP4_TrakAtom(unsigned int, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4TrakAtom.cpp:165:5
    #28 0x5c8e3b in AP4_TrakAtom::Create(unsigned int, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4TrakAtom.h:58:20
    #29 0x5c8e3b in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned int, unsigned int, unsigned long long, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:377
    #30 0x5c7fbd in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned long long&, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:220:14
    #31 0x60c561 in AP4_ContainerAtom::ReadChildren(AP4_AtomFactory&, AP4_ByteStream&, unsigned long long) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:193:12
    #32 0x60c099 in AP4_ContainerAtom::AP4_ContainerAtom(unsigned int, unsigned long long, bool, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4ContainerAtom.cpp:138:5
    #33 0x5521b0 in AP4_MoovAtom::AP4_MoovAtom(unsigned int, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4MoovAtom.cpp:79:5
    #34 0x5cad1d in AP4_MoovAtom::Create(unsigned int, AP4_ByteStream&, AP4_AtomFactory&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4MoovAtom.h:56:20
    #35 0x5cad1d in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned int, unsigned int, unsigned long long, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:357
    #36 0x5c7fbd in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, unsigned long long&, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:220:14
    #37 0x5c75c0 in AP4_AtomFactory::CreateAtomFromStream(AP4_ByteStream&, AP4_Atom*&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4AtomFactory.cpp:150:12
    #38 0x54ea2c in AP4_File::ParseStream(AP4_ByteStream&, AP4_AtomFactory&, bool) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4File.cpp:104:12
    #39 0x54f0fa in AP4_File::AP4_File(AP4_ByteStream&, bool) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4File.cpp:78:5
    #40 0x542552 in main /tmp/Bento4-1.5.0-617/Source/C++/Apps/Mp42Aac/Mp42Aac.cpp:242:32
    #41 0x7fe62e887680 in __libc_start_main /var/tmp/portage/sys-libs/glibc-2.23-r4/work/glibc-2.23/csu/../csu/libc-start.c:289
    #42 0x44f3f8 in _start (/usr/bin/mp42aac+0x44f3f8)

Address 0x7fe62b800e86 is located in stack of thread T0 at offset 6 in frame
    #0 0x57b2ef in AP4_VisualSampleEntry::ReadFields(AP4_ByteStream&) /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4SampleEntry.cpp:759

  This frame has 1 object(s):
    [32, 65) 'compressor_name'
HINT: this may be a false positive if your program uses some custom stack unwind mechanism or swapcontext
      (longjmp and C++ exceptions *are* supported)
SUMMARY: AddressSanitizer: stack-buffer-underflow /tmp/Bento4-1.5.0-617/Source/C++/Core/Ap4SampleEntry.cpp:780:40 in AP4_VisualSampleEntry::ReadFields(AP4_ByteStream&)
Shadow bytes around the buggy address:
  0x0ffd456f8180: f1 f1 f1 f1 00 f2 f2 f2 00 f3 f3 f3 00 00 00 00
  0x0ffd456f8190: f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5
  0x0ffd456f81a0: f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5
  0x0ffd456f81b0: f1 f1 f1 f1 00 f2 f2 f2 00 f3 f3 f3 00 00 00 00
  0x0ffd456f81c0: f1 f1 f1 f1 04 f2 00 f2 f2 f2 00 f3 f3 f3 f3 f3
=>0x0ffd456f81d0:[f1]f1 f1 f1 00 00 00 00 01 f3 f3 f3 f3 f3 f3 f3
  0x0ffd456f81e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0ffd456f81f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0ffd456f8200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0ffd456f8210: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0ffd456f8220: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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
==4435==ABORTING

Affected version:
1.5.0-617

Fixed version:
N/A

Commit fix:
https://github.com/axiomatic-systems/Bento4/commit/03d1222ab9c2ce779cdf01bdb96cdd69cbdcfeda

Credit:
This bug was discovered by Agostino Sarubbo of Gentoo.

CVE:
CVE-2017-14639

Reproducer:
https://github.com/asarubbo/poc/blob/master/00344-bento4-stackunderflow-AP4_VisualSampleEntry_ReadFields

Timeline:
2017-09-08: bug discovered and reported to upstream
2017-09-14: blog post about the issue
2017-09-21: CVE assigned

Note:
This bug was found with American Fuzzy Lop.
This bug was identified with bare metal servers donated by Packet. This work is also supported by the Core Infrastructure Initiative.

Permalink:

bento4: stack-based buffer underflow in AP4_VisualSampleEntry::ReadFields (Ap4SampleEntry.cpp)

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