graphicsmagick: use-after-free in CloseBlob (blob.c) (INCOMPLETE FIX FOR CVE-2017-11403)

Description:
graphicsmagick is a collection of tools and libraries for many image formats.

After some test I realized that the fix for CVE-2017-11403 was not enough, see also:

graphicsmagick: use-after-free in CloseBlob (blob.c)

The complete ASan output of the issue:

# gm identify $FILE
==20404==ERROR: AddressSanitizer: heap-use-after-free on address 0x6230000053c0 at pc 0x7fc01a253357 bp 0x7fffcd2d2630 sp 0x7fffcd2d2628
READ of size 8 at 0x6230000053c0 thread T0
    #0 0x7fc01a253356 in CloseBlob /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/blob.c:859:3
    #1 0x7fc013fbed77 in ReadMNGImage /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/coders/png.c:5144:11
    #2 0x7fc01a50ee88 in ReadImage /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/constitute.c:1607:13
    #3 0x7fc01a3a1f18 in ConvertImageCommand /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/command.c:4348:22
    #4 0x7fc01a3de0c5 in MagickCommand /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/command.c:8869:17
    #5 0x7fc01a48985b in GMCommandSingle /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/command.c:17396:10
    #6 0x7fc01a486991 in GMCommand /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/command.c:17449:16
    #7 0x7fc018cf1680 in __libc_start_main /var/tmp/portage/sys-libs/glibc-2.23-r4/work/glibc-2.23/csu/../csu/libc-start.c:289
    #8 0x419cd8 in _init (/usr/bin/gm+0x419cd8)

0x6230000053c0 is located 6848 bytes inside of 6856-byte region [0x623000003900,0x6230000053c8)
freed by thread T0 here:
    #0 0x4cf4d0 in __interceptor_cfree /var/tmp/portage/sys-libs/compiler-rt-sanitizers-4.0.1/work/compiler-rt-4.0.1.src/lib/asan/asan_malloc_linux.cc:55
    #1 0x7fc01a8f13d2 in MagickFree /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/memory.c:509:5
    #2 0x7fc01a7dc750 in DestroyImage /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/image.c:1277:3
    #3 0x7fc01a8a7cda in DestroyImageList /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/list.c:239:5
    #4 0x7fc013fbed6f in ReadMNGImage /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/coders/png.c:5143:11
    #5 0x7fc01a50ee88 in ReadImage /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/constitute.c:1607:13
    #6 0x7fc01a3a1f18 in ConvertImageCommand /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/command.c:4348:22
    #7 0x7fc01a3de0c5 in MagickCommand /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/command.c:8869:17
    #8 0x7fc01a48985b in GMCommandSingle /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/command.c:17396:10
    #9 0x7fc01a486991 in GMCommand /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/command.c:17449:16
    #10 0x7fc018cf1680 in __libc_start_main /var/tmp/portage/sys-libs/glibc-2.23-r4/work/glibc-2.23/csu/../csu/libc-start.c:289

previously allocated by thread T0 here:
    #0 0x4cf688 in malloc /var/tmp/portage/sys-libs/compiler-rt-sanitizers-4.0.1/work/compiler-rt-4.0.1.src/lib/asan/asan_malloc_linux.cc:66
    #1 0x7fc01a8f04d6 in MagickMalloc /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/memory.c:156:10
    #2 0x7fc01a7a6fa3 in AllocateImage /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/image.c:336:18
    #3 0x7fc013f7819a in ReadMNGImage /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/coders/png.c:3872:9
    #4 0x7fc01a50ee88 in ReadImage /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/constitute.c:1607:13
    #5 0x7fc01a3a1f18 in ConvertImageCommand /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/command.c:4348:22
    #6 0x7fc01a3de0c5 in MagickCommand /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/command.c:8869:17
    #7 0x7fc01a48985b in GMCommandSingle /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/command.c:17396:10
    #8 0x7fc01a486991 in GMCommand /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/command.c:17449:16
    #9 0x7fc018cf1680 in __libc_start_main /var/tmp/portage/sys-libs/glibc-2.23-r4/work/glibc-2.23/csu/../csu/libc-start.c:289

SUMMARY: AddressSanitizer: heap-use-after-free /var/tmp/portage/media-gfx/graphicsmagick-1.3.26/work/GraphicsMagick-1.3.26/magick/blob.c:859:3 in CloseBlob
Shadow bytes around the buggy address:
  0x0c467fff8a20: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x0c467fff8a30: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x0c467fff8a40: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x0c467fff8a50: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x0c467fff8a60: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
=>0x0c467fff8a70: fd fd fd fd fd fd fd fd[fd]fa fa fa fa fa fa fa
  0x0c467fff8a80: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c467fff8a90: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c467fff8aa0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c467fff8ab0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c467fff8ac0: 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
==20404==ABORTING

Affected version:
1.3.26

Fixed version:
N/A

Commit fix:
http://hg.code.sf.net/p/graphicsmagick/code/rev/98721124e51f

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

CVE:
CVE-2017-14103

Reproducer:
https://github.com/asarubbo/poc/blob/master/00333-graphicsmagick-UAF-CloseBlob

Timeline:
2017-08-02: bug discovered and reported to upstream
2017-08-27: upstream released a fix
2017-09-01: blog post about the issue
2017-09-01: 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:

graphicsmagick: use-after-free in CloseBlob (blob.c) (INCOMPLETE FIX FOR CVE-2017-11403)

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One Response to graphicsmagick: use-after-free in CloseBlob (blob.c) (INCOMPLETE FIX FOR CVE-2017-11403)

  1. Pingback: CVE-2017-14103 – 安百科技

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