The LZW decompressor in (1) the BufCompressedFill function in fontfile/decompress.c in X.Org libXfont before 1.4.4 and (2) compress/compress.c in 4.3BSD, as used in zopen.c in OpenBSD before 3.8, FreeBSD, NetBSD 4.0.x and 5.0.x before 5.0.3 and 5.1.x before 5.1.1, FreeType 2.1.9, and other products, does not properly handle code words that are absent from the decompression table when encountered, which allows context-dependent attackers to trigger an infinite loop or a heap-based buffer overflow, and possibly execute arbitrary code, via a crafted compressed stream, a related issue to CVE-2006-1168 and CVE-2011-2896.
http://cgit.freedesktop.org/xorg/lib/libXfont/commit/?id=d11ee5886e9d9ec610051a206b135a4cdc1e09a0
http://ftp.netbsd.org/pub/NetBSD/security/advisories/NetBSD-SA2011-007.txt.asc
http://lists.apple.com/archives/security-announce/2012/Feb/msg00000.html
http://lists.apple.com/archives/security-announce/2012/May/msg00001.html
http://lists.apple.com/archives/security-announce/2015/Dec/msg00000.html
http://lists.apple.com/archives/security-announce/2015/Dec/msg00001.html
http://lists.apple.com/archives/security-announce/2015/Dec/msg00002.html
http://lists.apple.com/archives/security-announce/2015/Dec/msg00005.html
http://lists.freedesktop.org/archives/xorg-announce/2011-August/001721.html
http://lists.freedesktop.org/archives/xorg-announce/2011-August/001722.html
http://lists.opensuse.org/opensuse-security-announce/2011-09/msg00019.html
http://lists.opensuse.org/opensuse-security-announce/2011-12/msg00004.html
http://secunia.com/advisories/45544
http://secunia.com/advisories/45568
http://secunia.com/advisories/45599
http://secunia.com/advisories/45986
http://secunia.com/advisories/46127
http://secunia.com/advisories/48951
http://securitytracker.com/id?1025920
http://support.apple.com/kb/HT5130
http://support.apple.com/kb/HT5281
http://www.debian.org/security/2011/dsa-2293
http://www.mandriva.com/security/advisories?name=MDVSA-2011:153
http://www.openbsd.org/cgi-bin/cvsweb/src/usr.bin/compress/zopen.c#rev1.17
http://www.openwall.com/lists/oss-security/2011/08/10/10
http://www.redhat.com/support/errata/RHSA-2011-1154.html
http://www.redhat.com/support/errata/RHSA-2011-1155.html
http://www.redhat.com/support/errata/RHSA-2011-1161.html
http://www.redhat.com/support/errata/RHSA-2011-1834.html
http://www.securityfocus.com/bid/49124
http://www.ubuntu.com/usn/USN-1191-1
https://bugzilla.redhat.com/show_bug.cgi?id=725760
https://bugzilla.redhat.com/show_bug.cgi?id=727624
https://exchange.xforce.ibmcloud.com/vulnerabilities/69141
https://support.apple.com/HT205635
https://support.apple.com/HT205637