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The recent exploit for the iPhone is reported [1],[2] to be related to freetype's handling of postscript type1 fonts. This vulnerability is caused due to an error within the t1_decoder_parse_charstrings() function (src/psaux/t1decode.c) and can be exploited to corrupt memory by tricking a user into processing a specially-crafted postscript type1 font in an application that uses the freetype library. The report indicates that the vulnerability is in version 2.4.5, but at a quick glance it also looks like 2.3.11 is affected, but not 2.2.x. Discussion is happening upstream with potential patches being discussed [3]. [1] http://secunia.com/advisories/45167 [2] http://lists.nongnu.org/archive/html/freetype-devel/2011-07/msg00014.html [3] http://lists.nongnu.org/archive/html/freetype-devel/2011-07/msg00015.html
This has been assigned CVE-2011-0226: http://thread.gmane.org/gmane.comp.security.oss.general/5494/focus=5500 Reference: http://support.apple.com/kb/HT4802
Following: http://esec-lab.sogeti.com/post/Analysis-of-the-jailbreakme-v3-font-exploit i extracted the font from the pdf file Running the font on ftview or ftbench under valgrind, it seems that there could a possibility of running arbitrary code, packaged as part of the charstings in the font. =7628== Conditional jump or move depends on uninitialised value(s) ==7628== at 0x43ED0357: psh_hint_table_activate_mask (pshalgo.c:326) ==7628== by 0x43ED2D31: ps_hints_apply (pshalgo.c:1730) ==7628== by 0x43EEF987: t1_decoder_parse_charstrings (t1decode.c:1082) ==7628== by 0x43EA480B: T1_Parse_Glyph_And_Get_Char_String (t1gload.c:93) ==7628== by 0x43EA64B6: T1_Load_Glyph (t1gload.c:350) ==7628== by 0x43E90A82: FT_Load_Glyph (ftobjs.c:683) ==7628== by 0x8049ADC: test_load (ftbench.c:221) ==7628== by 0x41D3895C: ??? You would probably need to adjust the payload a bit for linux?
Related upstream git commits: http://git.savannah.gnu.org/cgit/freetype/freetype2.git/commit/?id=c46b1e2476cc1804c0dd25d463be3c99d58befd7 http://git.savannah.gnu.org/cgit/freetype/freetype2.git/commit/?id=dc33b4a1555c184b83a402dfa1856b213e6b4fbd http://git.savannah.gnu.org/cgit/freetype/freetype2.git/commit/?id=60f8371353013e78ab0a789f49af90d64fe65f0d
Created freetype tracking bugs for this issue Affects: fedora-all [bug 723469]
This issue has been addressed in following products: Red Hat Enterprise Linux 6 Via RHSA-2011:1085 https://rhn.redhat.com/errata/RHSA-2011-1085.html