Red Hat Bugzilla – Bug 722701
CVE-2011-0226 freetype: postscript type1 font parsing vulnerability
Last modified: 2015-11-24 09:39:59 EST
The recent exploit for the iPhone is reported , 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 .
This has been assigned CVE-2011-0226:
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:
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