{"id":386,"date":"2016-08-01T14:57:45","date_gmt":"2016-08-01T12:57:45","guid":{"rendered":"http:\/\/blogs.gentoo.org\/ago\/?p=386"},"modified":"2016-09-07T14:36:05","modified_gmt":"2016-09-07T12:36:05","slug":"desktop-file-utils-desktop-file-validate-heap-based-buffer-overflow-in-validate-c","status":"publish","type":"post","link":"https:\/\/blogs.gentoo.org\/ago\/2016\/08\/01\/desktop-file-utils-desktop-file-validate-heap-based-buffer-overflow-in-validate-c\/","title":{"rendered":"desktop-file-utils: desktop-file-validate: heap-based buffer overflow in validate.c"},"content":{"rendered":"<p><strong>Description<\/strong>:<br \/>\n<a href=\"https:\/\/freedesktop.org\/wiki\/Software\/desktop-file-utils\">desktop-file-utils<\/a> is command line set of utilities to work with desktop menu entries<br \/>\nA fuzz against desktop-file-utils binary revealed that there was an heap overflow.<\/p>\n<p>The complete ASan output:<\/p>\n<pre><font size=\"2\"># desktop-file-validate crafted.desktop \r\n=================================================================\r\n==29796==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x60300000e843 at pc 0x0000004dda86 bp 0x7ffe7c643bd0 sp 0x7ffe7c643bc8\r\nREAD of size 1 at 0x60300000e843 thread T0\r\n    #0 0x4dda85 in handle_exec_key \/tmp\/portage\/dev-util\/desktop-file-utils-0.22\/work\/desktop-file-utils-0.22\/src\/validate.c:1229:10\r\n    #1 0x4da3b6 in validate_known_key \/tmp\/portage\/dev-util\/desktop-file-utils-0.22\/work\/desktop-file-utils-0.22\/src\/validate.c:2248:12\r\n    #2 0x4d9671 in validate_action_key \/tmp\/portage\/dev-util\/desktop-file-utils-0.22\/work\/desktop-file-utils-0.22\/src\/validate.c:2284:10\r\n    #3 0x4d9671 in validate_keys_for_current_group \/tmp\/portage\/dev-util\/desktop-file-utils-0.22\/work\/desktop-file-utils-0.22\/src\/validate.c:2376\r\n    #4 0x4d3c78 in validate_flush_parse_buffer \/tmp\/portage\/dev-util\/desktop-file-utils-0.22\/work\/desktop-file-utils-0.22\/src\/validate.c:2945:5\r\n    #5 0x4d3c78 in validate_parse_from_fd \/tmp\/portage\/dev-util\/desktop-file-utils-0.22\/work\/desktop-file-utils-0.22\/src\/validate.c:2993\r\n    #6 0x4d3c78 in validate_load_and_parse \/tmp\/portage\/dev-util\/desktop-file-utils-0.22\/work\/desktop-file-utils-0.22\/src\/validate.c:3011\r\n    #7 0x4d3c78 in desktop_file_validate \/tmp\/portage\/dev-util\/desktop-file-utils-0.22\/work\/desktop-file-utils-0.22\/src\/validate.c:3078\r\n    #8 0x4e5302 in main \/tmp\/portage\/dev-util\/desktop-file-utils-0.22\/work\/desktop-file-utils-0.22\/src\/validator.c:81:17\r\n    #9 0x7f0e05f6f854 in __libc_start_main \/tmp\/portage\/sys-libs\/glibc-2.21-r1\/work\/glibc-2.21\/csu\/libc-start.c:289\r\n    #10 0x4191f8 in _init (\/usr\/bin\/desktop-file-validate+0x4191f8)\r\n\r\n0x60300000e843 is located 0 bytes to the right of 19-byte region [0x60300000e830,0x60300000e843)\r\nallocated by thread T0 here:\r\n    #0 0x4a7f4b in malloc \/var\/tmp\/portage\/sys-devel\/llvm-3.7.1\/work\/llvm-3.7.1.src\/projects\/compiler-rt\/lib\/asan\/asan_malloc_linux.cc:40:3                                                                                                                                    \r\n    #1 0x7f0e06f2a653 in g_malloc \/tmp\/portage\/dev-libs\/glib-2.44.1-r1\/work\/glib-2.44.1\/glib\/gmem.c:97:13                                                                                                                                                                      \r\n                                                                                                                                                                                                                                                                               \r\nSUMMARY: AddressSanitizer: heap-buffer-overflow \/tmp\/portage\/dev-util\/desktop-file-utils-0.22\/work\/desktop-file-utils-0.22\/src\/validate.c:1229:10 in handle_exec_key                                                                                                           \r\nShadow bytes around the buggy address:                                                                                                                                                                                                                                         \r\n  0x0c067fff9cb0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa                                                                                                                                                                                                              \r\n  0x0c067fff9cc0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa                                                                                                                                                                                                              \r\n  0x0c067fff9cd0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa                                                                                                                                                                                                              \r\n  0x0c067fff9ce0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa                                                                                                                                                                                                              \r\n  0x0c067fff9cf0: fa fa fa fa 00 00 00 00 fa fa 00 00 00 00 fa fa                                                                                                                                                                                                              \r\n=&gt;0x0c067fff9d00: 00 00 00 03 fa fa 00 00[03]fa fa fa fd fd fd fa                                                                                                                                                                                                              \r\n  0x0c067fff9d10: fa fa fd fd fd fd fa fa fd fd fd fa fa fa fd fd                                                                                                                                                                                                              \r\n  0x0c067fff9d20: fd fd fa fa fd fd fd fd fa fa fd fd fd fd fa fa                                                                                                                                                                                                              \r\n  0x0c067fff9d30: fd fd fd fa fa fa fd fd fd fa fa fa fd fd fd fd                                                                                                                                                                                                              \r\n  0x0c067fff9d40: fa fa fd fd fd fd fa fa fd fd fd fd fa fa fd fd                                                                                                                                                                                                              \r\n  0x0c067fff9d50: fd fd fa fa fd fd fd fd fa fa fd fd fd fd 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==29796==ABORTING\r\n<\/font><\/pre>\n<p><strong>Affected version:<\/strong><br \/>\nAll, tested on 0.22<\/p>\n<p><strong>Fixed version:<\/strong><br \/>\n0.23<\/p>\n<p><strong>Commit fix:<\/strong><br \/>\n<a href=\"https:\/\/cgit.freedesktop.org\/xdg\/desktop-file-utils\/commit\/?id=cddcd6612b66cb3963920b5f2734850a217d7020\">https:\/\/cgit.freedesktop.org\/xdg\/desktop-file-utils\/commit\/?id=cddcd6612b66cb3963920b5f2734850a217d7020<\/a><\/p>\n<p><strong>Credit:<\/strong><br \/>\nThis bug was discovered by Agostino Sarubbo of Gentoo.<\/p>\n<p><strong>Timeline:<\/strong><br \/>\n2016-02-16: bug discovered<br \/>\n2016-02-16: downstream report (Gentoo)<br \/>\n2016-02-26: upstream report<br \/>\n2016-02-29: upstream released a fix<br \/>\n2016-08-01: blog post about the issue<\/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=\"MFB6gwsFa1\" class=\"wp-embedded-content\"><p><a href=\"http:\/\/blogs.gentoo.org\/ago\/2016\/08\/01\/desktop-file-utils-desktop-file-validate-heap-based-buffer-overflow-in-validate-c\/\">desktop-file-utils: desktop-file-validate: heap-based buffer overflow in validate.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\/2016\/08\/01\/desktop-file-utils-desktop-file-validate-heap-based-buffer-overflow-in-validate-c\/embed\/#?secret=MFB6gwsFa1\" data-secret=\"MFB6gwsFa1\" width=\"600\" height=\"338\" title=\"&#8220;desktop-file-utils: desktop-file-validate: heap-based buffer overflow in validate.c&#8221; &#8212; agostino&#039;s blog\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Description: desktop-file-utils is command line set of utilities to work with desktop menu entries A fuzz against desktop-file-utils binary revealed that there was an heap overflow. The complete ASan output: # desktop-file-validate crafted.desktop ================================================================= ==29796==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x60300000e843 &hellip; <a href=\"https:\/\/blogs.gentoo.org\/ago\/2016\/08\/01\/desktop-file-utils-desktop-file-validate-heap-based-buffer-overflow-in-validate-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-6e","_links":{"self":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/386"}],"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=386"}],"version-history":[{"count":3,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/386\/revisions"}],"predecessor-version":[{"id":389,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/386\/revisions\/389"}],"wp:attachment":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/media?parent=386"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/categories?post=386"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/tags?post=386"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}