{"id":2141,"date":"2017-09-07T16:07:38","date_gmt":"2017-09-07T14:07:38","guid":{"rendered":"http:\/\/blogs.gentoo.org\/ago\/?p=2141"},"modified":"2017-09-07T17:29:57","modified_gmt":"2017-09-07T15:29:57","slug":"aacplusenc-null-pointer-dereference-in-deletebitbuffer-bitbuffer-c","status":"publish","type":"post","link":"https:\/\/blogs.gentoo.org\/ago\/2017\/09\/07\/aacplusenc-null-pointer-dereference-in-deletebitbuffer-bitbuffer-c\/","title":{"rendered":"aacplusenc: NULL pointer dereference in DeleteBitBuffer (bitbuffer.c)"},"content":{"rendered":"<p><strong>Description<\/strong>:<br \/>\n<a href=\"https:\/\/github.com\/teknoraver\/aacplusenc\">aacplusenc<\/a> is an High-Efficiency AAC (AAC+) Encoder.<\/p>\n<p>The complete ASan output of the issue:<\/p>\n<pre><font size=\"2\"># aacplusenc $FILE out.aac 32\r\n                                                                                                                                                                                                                  \r\n*************************************************************                                                                                                                                                     \r\n* Enhanced aacPlus Encoder                                                                                                                                                                                        \r\n* Build Aug 30 2017, 14:40:49                                                                                                                                                                                     \r\n* Matteo Croce                                                                                                                                                                                \r\n*************************************************************                                                                                                                                                     \r\n                                                                                                                                                                                                                  \r\ninput file 101.crashes.wav:                                                                                                                                                                                       \r\nsr = 48000, nc = 1                                                                                                                                                                                                \r\n                                                                                                                                                                                                                  \r\noutput file out.aac:                                                                                                                                                                                              \r\nbr = 32000 sr-OUT = 48000  nc-OUT = 1                                                                                                                                                                             \r\n                                                                                                                                                                                                                  \r\n                                                                                                                                                                                                                  \r\nASAN:DEADLYSIGNAL\r\n=================================================================\r\n==21496==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000030 (pc 0x000000562e2f bp 0x7ffc2ec32430 sp 0x7ffc2ec32430 T0)\r\n==21496==The signal is caused by a WRITE memory access.\r\n==21496==Hint: address points to the zero page.\r\n    #0 0x562e2e in DeleteBitBuffer \/var\/tmp\/portage\/media-sound\/aacplusenc-0.17.5\/work\/aacplusenc\/libbitbuf\/bitbuffer.c:97:23\r\n    #1 0x50d909 in AacEncClose \/var\/tmp\/portage\/media-sound\/aacplusenc-0.17.5\/work\/aacplusenc\/libaacenc\/aacenc.c:469:5\r\n    #2 0x50c0df in main \/var\/tmp\/portage\/media-sound\/aacplusenc-0.17.5\/work\/aacplusenc\/aacplusenc.c:536:2\r\n    #3 0x7f0e4c21b680 in __libc_start_main \/var\/tmp\/portage\/sys-libs\/glibc-2.23-r4\/work\/glibc-2.23\/csu\/..\/csu\/libc-start.c:289\r\n    #4 0x419e78 in _init (\/usr\/bin\/aacplusenc+0x419e78)\r\n\r\nAddressSanitizer can not provide additional info.\r\nSUMMARY: AddressSanitizer: SEGV \/var\/tmp\/portage\/media-sound\/aacplusenc-0.17.5\/work\/aacplusenc\/libbitbuf\/bitbuffer.c:97:23 in DeleteBitBuffer\r\n==21496==ABORTING\r\n<\/font><\/pre>\n<p><strong>Affected version:<\/strong><br \/>\n0.17.5<\/p>\n<p><strong>Fixed version:<\/strong><br \/>\nN\/A<\/p>\n<p><strong>Commit fix:<\/strong><br \/>\nN\/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-2017-14181<\/p>\n<p><strong>Reproducer:<\/strong><br \/>\n<a href=\"https:\/\/github.com\/asarubbo\/poc\/blob\/master\/00332-aacplusenc-NULLptr-DeleteBitBuffer\">https:\/\/github.com\/asarubbo\/poc\/blob\/master\/00332-aacplusenc-NULLptr-DeleteBitBuffer<\/a><\/p>\n<p><strong>Timeline:<\/strong><br \/>\n2017-08-31: bug discovered and reported to upstream<br \/>\n2017-09-07: blog post about the issue<br \/>\n2017-09-07: 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>.<br \/>\nThis bug was identified with bare metal servers donated by <a href=\"https:\/\/www.packet.net\/\">Packet<\/a>. This work is also supported by the <a href=\"https:\/\/www.coreinfrastructure.org\">Core Infrastructure Initiative<\/a>.<\/p>\n<p><strong>Permalink:<\/strong><\/p>\n<blockquote data-secret=\"FFsylia7Ca\" class=\"wp-embedded-content\"><p><a href=\"http:\/\/blogs.gentoo.org\/ago\/2017\/09\/07\/aacplusenc-null-pointer-dereference-in-deletebitbuffer-bitbuffer-c\/\">aacplusenc: NULL pointer dereference in DeleteBitBuffer (bitbuffer.c)<\/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\/2017\/09\/07\/aacplusenc-null-pointer-dereference-in-deletebitbuffer-bitbuffer-c\/embed\/#?secret=FFsylia7Ca\" data-secret=\"FFsylia7Ca\" width=\"600\" height=\"338\" title=\"&#8220;aacplusenc: NULL pointer dereference in DeleteBitBuffer (bitbuffer.c)&#8221; &#8212; agostino&#039;s blog\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Description: aacplusenc is an High-Efficiency AAC (AAC+) Encoder. The complete ASan output of the issue: # aacplusenc $FILE out.aac 32 ************************************************************* * Enhanced aacPlus Encoder * Build Aug 30 2017, 14:40:49 * Matteo Croce ************************************************************* input file 101.crashes.wav: sr = &hellip; <a href=\"https:\/\/blogs.gentoo.org\/ago\/2017\/09\/07\/aacplusenc-null-pointer-dereference-in-deletebitbuffer-bitbuffer-c\/\">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-yx","_links":{"self":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/2141"}],"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=2141"}],"version-history":[{"count":2,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/2141\/revisions"}],"predecessor-version":[{"id":2143,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/2141\/revisions\/2143"}],"wp:attachment":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/media?parent=2141"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/categories?post=2141"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/tags?post=2141"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}