[BZ#2767] A heap-buffer-overflow in libtiff 4.0.8.

Submitted by xiaosatianyu at 126 dot com on 2017-12-27 07:28

Description

Created an attachment (id=835)
poc

There is a heap-buffer-overflow in PackBitsEncode function tif_packbits.c line 88 in libtiff 4.0.8.
=================================================================
==23471==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x619000000980 at pc 0x0000006eedf5 bp 0x7fffa9c16820 sp 0x7fffa9c16818
READ of size 1 at 0x619000000980 thread T0
    #0 0x6eedf4 in PackBitsEncode /home/xiaosatianyu/workspace/git/fuzz/for-new-CVE/benlibtiff/libtiff/libtiff/tif_packbits.c:88:25
    #1 0x61a451 in TIFFWriteScanline /home/xiaosatianyu/workspace/git/fuzz/for-new-CVE/benlibtiff/libtiff/libtiff/tif_write.c:173:11
    #2 0x530827 in main /home/xiaosatianyu/workspace/git/fuzz/for-new-CVE/benlibtiff/libtiff/tools/bmp2tiff.c:775:9
    #3 0x7f70dbcbef44 in __libc_start_main /build/eglibc-SvCtMH/eglibc-2.19/csu/libc-start.c:287
    #4 0x41c8cb in _start (/home/binzhang/Desktop/bmp2tiff/bmp2tiff+0x41c8cb)

0x619000000980 is located 0 bytes to the right of 1024-byte region [0x619000000580,0x619000000980)
allocated by thread T0 here:
    #0 0x4f55d6 in __interceptor_malloc /home/xiaosatianyu/workspace/git/LLVM/llvm/projects/compiler-rt/lib/asan/asan_malloc_linux.cc:88
    #1 0x6274b0 in _TIFFmalloc /home/xiaosatianyu/workspace/git/fuzz/for-new-CVE/benlibtiff/libtiff/libtiff/tif_unix.c:316:10
    #2 0x52e5dd in main /home/xiaosatianyu/workspace/git/fuzz/for-new-CVE/benlibtiff/libtiff/tools/bmp2tiff.c:678:34
    #3 0x7f70dbcbef44 in __libc_start_main /build/eglibc-SvCtMH/eglibc-2.19/csu/libc-start.c:287

SUMMARY: AddressSanitizer: heap-buffer-overflow /home/xiaosatianyu/workspace/git/fuzz/for-new-CVE/benlibtiff/libtiff/libtiff/tif_packbits.c:88:25 in PackBitsEncode
Shadow bytes around the buggy address:
  0x0c327fff80e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c327fff80f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c327fff8100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c327fff8110: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c327fff8120: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x0c327fff8130:[fa]fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c327fff8140: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c327fff8150: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c327fff8160: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c327fff8170: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c327fff8180: 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
==23471==ABORTING
Attachment 835, "poc":
report-1
URL : https://github.com/xiaosatianyu/for-cve/blob/master/collect_poc/libtiff4.0.8/bmp2tiff/cve-2017-17942/cve-2017-17942-poc