CVE-2019-19948: heap-buffer-overflow in WriteSGIImage of coders/sgi.c · Issue #1562 · ImageMagick/ImageMagick

Prerequisites

• I have written a descriptive issue title
• I have verified that I am using the latest version of ImageMagick
• I have searched open and closed issues to ensure it has not already been reported

Description

There is a heap buffer overflow vulnerability in function WriteSGIImage of coders/sgi.c.

Steps to Reproduce

poc
magick convert $poc ./test.sgi
=================================================================
==41720==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7f70c67db7f8 at pc 0x0000006c216f bp 0x7ffea64ddb50 sp 0x7ffea64ddb40
WRITE of size 1 at 0x7f70c67db7f8 thread T0
#0 0x6c216e in WriteSGIImage coders/sgi.c:1051
#1 0x849036 in WriteImage MagickCore/constitute.c:1159
#2 0x849d5b in WriteImages MagickCore/constitute.c:1376
#3 0xbf16d0 in ConvertImageCommand MagickWand/convert.c:3305
#4 0xcdf180 in MagickCommandGenesis MagickWand/mogrify.c:185
#5 0x4100a1 in MagickMain utilities/magick.c:149
#6 0x410282 in main utilities/magick.c:180
#7 0x7f70c10c882f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2082f)
#8 0x40fbb8 in _start (/home/test/temp/ImageMagick/utilities/magick+0x40fbb8)

0x7f70c67db7f8 is located 8 bytes to the left of 524288-byte region [0x7f70c67db800,0x7f70c685b800)
allocated by thread T0 here:
#0 0x7f70c5868076 in __interceptor_posix_memalign (/usr/lib/x86_64-linux-gnu/libasan.so.2+0x99076)
#1 0x4408c7 in AcquireAlignedMemory MagickCore/memory.c:265
#2 0x440beb in AcquireVirtualMemory MagickCore/memory.c:621
#3 0x6c1ead in WriteSGIImage coders/sgi.c:1030
#4 0x849036 in WriteImage MagickCore/constitute.c:1159
#5 0x849d5b in WriteImages MagickCore/constitute.c:1376
#6 0xbf16d0 in ConvertImageCommand MagickWand/convert.c:3305
#7 0xcdf180 in MagickCommandGenesis MagickWand/mogrify.c:185
#8 0x4100a1 in MagickMain utilities/magick.c:149
#9 0x410282 in main utilities/magick.c:180
#10 0x7f70c10c882f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2082f)

SUMMARY: AddressSanitizer: heap-buffer-overflow coders/sgi.c:1051 WriteSGIImage
Shadow bytes around the buggy address:
0x0fee98cf36a0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0fee98cf36b0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0fee98cf36c0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0fee98cf36d0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0fee98cf36e0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
=>0x0fee98cf36f0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa[fa]
0x0fee98cf3700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0fee98cf3710: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0fee98cf3720: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0fee98cf3730: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0fee98cf3740: 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
Heap right redzone: fb
Freed heap region: fd
Stack left redzone: f1
Stack mid redzone: f2
Stack right redzone: f3
Stack partial redzone: f4
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
==41720==ABORTING

System Configuration

• ImageMagick version:
  Version: ImageMagick 7.0.8-43 Q16 x86_64 2019-04-29 https://imagemagick.org
  Copyright: ? 1999-2019 ImageMagick Studio LLC
  License: https://imagemagick.org/script/license.php
  Features: Cipher DPC HDRI OpenMP(4.0)
  Delegates (built-in): bzlib djvu fftw fontconfig freetype jbig jng jpeg lcms lqr lzma openexr pangocairo png tiff wmf x xml zlib
• Environment (Operating system, version and so on):
  Distributor ID: Ubuntu
  Description: Ubuntu 16.04.1 LTS
  Release: 16.04
  Codename: xenial
• Additional information: