syoyo/tinyexr

heap overflow in tinyexr::DecodePixelData

sleicasper opened this issue · 8 comments

desc

There is a heap based buffer overflow in tinyexr::DecodePixelData before 20220506 that could cause remote code execution depending on the usage of this program.

asan output

==2363537==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x629000009210 at pc 0x000000563bd4 bp 0x7fffffffc4b0 sp 0x7fffffffc4a8
READ of size 1 at 0x629000009210 thread T0
    #0 0x563bd3 in tinyexr::cpy4(float*, float const*) /tinyexr/./BUILD/tinyexr.h:759:12
    #1 0x563bd3 in tinyexr::DecodePixelData(unsigned char**, int const*, unsigned char const*, unsigned long, int, int, int, int, int, int, int, int, unsigned long, unsigned long, TEXRAttribute const*, unsigned long, TEXRChannelInfo const*, std::vector<unsigned long, std::allocator<unsigned long> > const&) /tinyexr/./BUILD/tinyexr.h:3593:13
    #2 0x505f79 in tinyexr::DecodeTiledPixelData(unsigned char**, int*, int*, int const*, unsigned char const*, unsigned long, int, int, int, int, int, int, int, int, unsigned long, unsigned long, TEXRAttribute const*, unsigned long, TEXRChannelInfo const*, std::vector<unsigned long, std::allocator<unsigned long> > const&) /tinyexr/./BUILD/tinyexr.h:4115:10
    #3 0x505f79 in tinyexr::DecodeTiledLevel(TEXRImage*, TEXRHeader const*, tinyexr::OffsetData const&, std::vector<unsigned long, std::allocator<unsigned long> > const&, int, unsigned char const*, unsigned long, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*) /tinyexr/./BUILD/tinyexr.h:4841:16
    #4 0x504abc in tinyexr::DecodeChunk(TEXRImage*, TEXRHeader const*, tinyexr::OffsetData const&, unsigned char const*, unsigned long, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*) /tinyexr/./BUILD/tinyexr.h:5015:19
    #5 0x519246 in tinyexr::DecodeEXRImage(TEXRImage*, TEXRHeader const*, unsigned char const*, unsigned char const*, unsigned long, char const**) /tinyexr/./BUILD/tinyexr.h:5756:15
    #6 0x519246 in LoadEXRImageFromMemory /tinyexr/./BUILD/tinyexr.h:6444:10
    #7 0x53f3bf in LLVMFuzzerTestOneInput /tinyexr/./SRC/test/fuzzer/fuzz.cc:20:9
    #8 0x4fbaad in fuzzfile(char*) /tinyexr/../../../harness/aflharness.cc:35:5
    #9 0x4fbc06 in main /tinyexr/../../../harness/aflharness.cc:52:13
    #10 0x7ffff7a51082 in __libc_start_main /build/glibc-SzIz7B/glibc-2.31/csu/../csu/libc-start.c:308:16
    #11 0x41e65d in _start (/tinyexr/fuzzrun/harness+0x41e65d)

0x629000009210 is located 0 bytes to the right of 16400-byte region [0x629000005200,0x629000009210)
allocated by thread T0 here:
    #0 0x4f8c17 in operator new(unsigned long) /fuzz/fuzzdeps/llvm-project-11.0.0/compiler-rt/lib/asan/asan_new_delete.cpp:99:3
    #1 0x55b2b2 in __gnu_cxx::new_allocator<unsigned char>::allocate(unsigned long, void const*) /usr/lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/ext/new_allocator.h:114:27
    #2 0x55b2b2 in std::allocator_traits<std::allocator<unsigned char> >::allocate(std::allocator<unsigned char>&, unsigned long) /usr/lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/alloc_traits.h:443:20
    #3 0x55b2b2 in std::_Vector_base<unsigned char, std::allocator<unsigned char> >::_M_allocate(unsigned long) /usr/lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/stl_vector.h:343:20
    #4 0x55b2b2 in std::_Vector_base<unsigned char, std::allocator<unsigned char> >::_M_create_storage(unsigned long) /usr/lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/stl_vector.h:358:33
    #5 0x55b2b2 in std::_Vector_base<unsigned char, std::allocator<unsigned char> >::_Vector_base(unsigned long, std::allocator<unsigned char> const&) /usr/lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/stl_vector.h:302:9
    #6 0x55b2b2 in std::vector<unsigned char, std::allocator<unsigned char> >::vector(unsigned long, std::allocator<unsigned char> const&) /usr/lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/stl_vector.h:508:9
    #7 0x55b2b2 in tinyexr::DecodePixelData(unsigned char**, int const*, unsigned char const*, unsigned long, int, int, int, int, int, int, int, int, unsigned long, unsigned long, TEXRAttribute const*, unsigned long, TEXRChannelInfo const*, std::vector<unsigned long, std::allocator<unsigned long> > const&) /tinyexr/./BUILD/tinyexr.h:3484:32
    #8 0x505f79 in tinyexr::DecodeTiledPixelData(unsigned char**, int*, int*, int const*, unsigned char const*, unsigned long, int, int, int, int, int, int, int, int, unsigned long, unsigned long, TEXRAttribute const*, unsigned long, TEXRChannelInfo const*, std::vector<unsigned long, std::allocator<unsigned long> > const&) /tinyexr/./BUILD/tinyexr.h:4115:10
    #9 0x505f79 in tinyexr::DecodeTiledLevel(TEXRImage*, TEXRHeader const*, tinyexr::OffsetData const&, std::vector<unsigned long, std::allocator<unsigned long> > const&, int, unsigned char const*, unsigned long, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*) /tinyexr/./BUILD/tinyexr.h:4841:16

SUMMARY: AddressSanitizer: heap-buffer-overflow /tinyexr/./BUILD/tinyexr.h:759:12 in tinyexr::cpy4(float*, float const*)
Shadow bytes around the buggy address:
  0x0c527fff91f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c527fff9200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c527fff9210: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c527fff9220: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c527fff9230: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x0c527fff9240: 00 00[fa]fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c527fff9250: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c527fff9260: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c527fff9270: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c527fff9280: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c527fff9290: 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
==2363537==ABORTING

reproduce

  • compile this project using address sanitizer
  • run ./test/fuzzer ./poc
syoyo commented

No issue observed in master 0c48a75

$ clang++ -fsanitize=address -Wno-padded -Weverything -Werror -Wall -Wextra -std=c++11 -g -O0 -DTINYEXR_USE_MINIZ=1 -DTINYEXR_USE_PIZ=1 -I./deps/miniz -o test_tinyexr test_tinyexr.cc miniz.o
$ ./test_tinyexr poc 
Header err. code -1

Well, I can still reproduce this issue

syoyo commented

You need to post compilation procedure in detail.

You need to post compilation procedure in detail.

clang -c deps/miniz/miniz.c -o miniz.o
clang++ -fsanitize=address -Wno-padded -Weverything -Werror -Wall -Wextra -std=c++11 -g -O0 -DTINYEXR_USE_MINIZ=1 -DTINYEXR_USE_PIZ=1 -I./deps/miniz -o test_tinyexr test_tinyexr.cc miniz.o
./test_tinyexr poc 

syoyo commented
clang++ -fsanitize=address -Wno-padded -Weverything -Werror -Wall -Wextra -std=c++11 -g -O0 -DTINYEXR_USE_MINIZ=1 -DTINYEXR_USE_PIZ=1 -I./deps/miniz -o test_tinyexr test_tinyexr.cc miniz.o
./test_tinyexr poc 

Still no issue with it. Reports Header err. code -1

Found you are attaching wrong POC file. Seems a Core audio file? Magic header starts with caff

image

clang++ -fsanitize=address -Wno-padded -Weverything -Werror -Wall -Wextra -std=c++11 -g -O0 -DTINYEXR_USE_MINIZ=1 -DTINYEXR_USE_PIZ=1 -I./deps/miniz -o test_tinyexr test_tinyexr.cc miniz.o
./test_tinyexr poc 

Still no issue with it. Reports Header err. code -1

Found you are attaching wrong POC file. Seems a Core audio file? Magic header starts with caff

image

your are right.

new poc:

poc.zip

syoyo commented

Thanks! Confirmed the issue is now reproducible.

Your PR to fix the issue is much appreciated.

syoyo commented

Close the issue to avoid CVE FUD