{"id":915,"date":"2016-11-19T16:20:32","date_gmt":"2016-11-19T14:20:32","guid":{"rendered":"http:\/\/blogs.gentoo.org\/ago\/?p=915"},"modified":"2016-11-23T10:47:24","modified_gmt":"2016-11-23T08:47:24","slug":"imagemagick-heap-based-buffer-overflow-in-ispixelgray-pixel-accessor-h","status":"publish","type":"post","link":"https:\/\/blogs.gentoo.org\/ago\/2016\/11\/19\/imagemagick-heap-based-buffer-overflow-in-ispixelgray-pixel-accessor-h\/","title":{"rendered":"imagemagick: heap-based buffer overflow in IsPixelGray (pixel-accessor.h)"},"content":{"rendered":"<p><strong>Description<\/strong>:<br \/>\n<a href=\"http:\/\/www.imagemagick.org\/script\/index.php\">imagemagick<\/a> is a software suite to create, edit, compose, or convert bitmap images.<\/p>\n<p>A fuzz on an updated version revealed another overflow.<\/p>\n<p>The complete ASan output:<\/p>\n<pre><font size=\"2\"># identify $FILE\r\n=================================================================\r\n==696==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x611000009700 at pc 0x7f300036c9a3 bp 0x7fff6e225970 sp 0x7fff6e225968\r\nREAD of size 4 at 0x611000009700 thread T0\r\n    #0 0x7f300036c9a2 in IsPixelGray \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/.\/MagickCore\/pixel-accessor.h:507:30\r\n    #1 0x7f300036c9a2 in IdentifyImageGray \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickCore\/attribute.c:677\r\n    #2 0x7f300036f0dd in IdentifyImageType \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickCore\/attribute.c:821:7\r\n    #3 0x7f300090c1da in IdentifyImage \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickCore\/identify.c:527:8\r\n    #4 0x7f2fff364075 in IdentifyImageCommand \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickWand\/identify.c:336:22\r\n    #5 0x7f2fff4afeca in MagickCommandGenesis \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickWand\/mogrify.c:183:14\r\n    #6 0x50a339 in MagickMain \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/utilities\/magick.c:145:10\r\n    #7 0x50a339 in main \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/utilities\/magick.c:176\r\n    #8 0x7f2ffd99c61f in __libc_start_main \/var\/tmp\/portage\/sys-libs\/glibc-2.22-r4\/work\/glibc-2.22\/csu\/libc-start.c:289\r\n    #9 0x419d28 in _init (\/usr\/bin\/magick+0x419d28)\r\n\r\n0x611000009700 is located 0 bytes to the right of 192-byte region [0x611000009640,0x611000009700)\r\nallocated by thread T0 here:\r\n    #0 0x4d3685 in posix_memalign \/tmp\/portage\/sys-devel\/llvm-3.9.0-r1\/work\/llvm-3.9.0.src\/projects\/compiler-rt\/lib\/asan\/asan_malloc_linux.cc:130\r\n    #1 0x7f3000a466b0 in AcquireAlignedMemory \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickCore\/memory.c:258:7\r\n    #2 0x7f300043addf in AcquireCacheNexusPixels \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickCore\/cache.c:4636:33\r\n    #3 0x7f3000402030 in SetPixelCacheNexusPixels \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickCore\/cache.c:4748:14\r\n    #4 0x7f30003e7d2d in GetVirtualPixelsFromNexus \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickCore\/cache.c:2629:10\r\n    #5 0x7f3000444e53 in GetCacheViewVirtualPixels \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickCore\/cache-view.c:664:10\r\n    #6 0x7f300036b27c in IdentifyImageGray \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickCore\/attribute.c:672:7\r\n    #7 0x7f300036f0dd in IdentifyImageType \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickCore\/attribute.c:821:7\r\n    #8 0x7f300090c1da in IdentifyImage \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickCore\/identify.c:527:8\r\n    #9 0x7f2fff364075 in IdentifyImageCommand \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickWand\/identify.c:336:22\r\n    #10 0x7f2fff4afeca in MagickCommandGenesis \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/MagickWand\/mogrify.c:183:14\r\n    #11 0x50a339 in MagickMain \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/utilities\/magick.c:145:10\r\n    #12 0x50a339 in main \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/utilities\/magick.c:176\r\n    #13 0x7f2ffd99c61f in __libc_start_main \/var\/tmp\/portage\/sys-libs\/glibc-2.22-r4\/work\/glibc-2.22\/csu\/libc-start.c:289\r\n\r\nSUMMARY: AddressSanitizer: heap-buffer-overflow \/tmp\/portage\/media-gfx\/imagemagick-7.0.3.6\/work\/ImageMagick-7.0.3-6\/.\/MagickCore\/pixel-accessor.h:507:30 in IsPixelGray\r\nShadow bytes around the buggy address:\r\n  0x0c227fff9290: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa\r\n  0x0c227fff92a0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa\r\n  0x0c227fff92b0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa\r\n  0x0c227fff92c0: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00\r\n  0x0c227fff92d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00\r\n=&gt;0x0c227fff92e0:[fa]fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa\r\n  0x0c227fff92f0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd\r\n  0x0c227fff9300: fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa\r\n  0x0c227fff9310: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00\r\n  0x0c227fff9320: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00\r\n  0x0c227fff9330: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa\r\nShadow byte legend (one shadow byte represents 8 application bytes):\r\n  Addressable:           00\r\n  Partially addressable: 01 02 03 04 05 06 07 \r\n  Heap left redzone:       fa\r\n  Heap right redzone:      fb\r\n  Freed heap region:       fd\r\n  Stack left redzone:      f1\r\n  Stack mid redzone:       f2\r\n  Stack right redzone:     f3\r\n  Stack partial redzone:   f4\r\n  Stack after return:      f5\r\n  Stack use after scope:   f8\r\n  Global redzone:          f9\r\n  Global init order:       f6\r\n  Poisoned by user:        f7\r\n  Container overflow:      fc\r\n  Array cookie:            ac\r\n  Intra object redzone:    bb\r\n  ASan internal:           fe\r\n  Left alloca redzone:     ca\r\n  Right alloca redzone:    cb\r\n==696==ABORTING\r\n<\/font><\/pre>\n<p><strong>Affected version:<\/strong><br \/>\n7.0.3.6<\/p>\n<p><strong>Fixed version:<\/strong><br \/>\n7.0.3.8<\/p>\n<p><strong>Commit fix:<\/strong><br \/>\n<a href=\"https:\/\/github.com\/ImageMagick\/ImageMagick\/commit\/ce98a7acbcfca7f0a178f4b1e7b957e419e0cc99\">https:\/\/github.com\/ImageMagick\/ImageMagick\/commit\/ce98a7acbcfca7f0a178f4b1e7b957e419e0cc99<\/a><\/p>\n<p><strong>Credit:<\/strong><br \/>\nThis bug was discovered by Agostino Sarubbo of Gentoo.<\/p>\n<p><strong>CVE:<\/strong><br \/>\nCVE-2016-9556<\/p>\n<p><strong>Reproducer:<\/strong><br \/>\n<a href=\"https:\/\/github.com\/asarubbo\/poc\/blob\/master\/00051-imagemagick-heapoverflow-IsPixelGray\">https:\/\/github.com\/asarubbo\/poc\/blob\/master\/00051-imagemagick-heapoverflow-IsPixelGray<\/a><\/p>\n<p><strong>Timeline:<\/strong><br \/>\n2016-11-16: bug discovered and reported to upstream<br \/>\n2016-11-17: upstream released a patch<br \/>\n2016-11-19: blog post about the issue<br \/>\n2016-11-23: CVE assigned<\/p>\n<p><strong>Note:<\/strong><br \/>\nThis bug was found with <a href=\"http:\/\/lcamtuf.coredump.cx\/afl\">American Fuzzy Lop<\/a>.<\/p>\n<p><strong>Permalink:<\/strong><\/p>\n<blockquote data-secret=\"LNQECE0sYA\" class=\"wp-embedded-content\"><p><a href=\"http:\/\/blogs.gentoo.org\/ago\/2016\/11\/19\/imagemagick-heap-based-buffer-overflow-in-ispixelgray-pixel-accessor-h\/\">imagemagick: heap-based buffer overflow in IsPixelGray (pixel-accessor.h)<\/a><\/p><\/blockquote>\n<p><iframe class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; clip: rect(1px, 1px, 1px, 1px);\" src=\"http:\/\/blogs.gentoo.org\/ago\/2016\/11\/19\/imagemagick-heap-based-buffer-overflow-in-ispixelgray-pixel-accessor-h\/embed\/#?secret=LNQECE0sYA\" data-secret=\"LNQECE0sYA\" width=\"600\" height=\"338\" title=\"&#8220;imagemagick: heap-based buffer overflow in IsPixelGray (pixel-accessor.h)&#8221; &#8212; agostino&#039;s blog\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Description: imagemagick is a software suite to create, edit, compose, or convert bitmap images. A fuzz on an updated version revealed another overflow. The complete ASan output: # identify $FILE ================================================================= ==696==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x611000009700 at pc 0x7f300036c9a3 &hellip; <a href=\"https:\/\/blogs.gentoo.org\/ago\/2016\/11\/19\/imagemagick-heap-based-buffer-overflow-in-ispixelgray-pixel-accessor-h\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":140,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":"","jetpack_publicize_message":"","jetpack_is_tweetstorm":false,"jetpack_publicize_feature_enabled":true},"categories":[12,10],"tags":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p2EaBc-eL","_links":{"self":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/915"}],"collection":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/users\/140"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/comments?post=915"}],"version-history":[{"count":5,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/915\/revisions"}],"predecessor-version":[{"id":966,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/915\/revisions\/966"}],"wp:attachment":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/media?parent=915"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/categories?post=915"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/tags?post=915"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}