The WebGL implementation in Mozilla Firefox before 15.0, Firefox ESR 10.x before 10.0.7, Thunderbird before 15.0, Thunderbird ESR 10.x before 10.0.7, and SeaMonkey before 2.12 on Linux, when a large number of sampler uniforms are used, does not properly interact with Mesa drivers, which allows remote attackers to execute arbitrary code or cause a denial of service (stack memory corruption) via a crafted web site.
http://www.xerox.com/download/security/security-bulletin/16287-4d6b7b0c81f7b/cert_XRX13-003_v1.0.pdf
http://www.ubuntu.com/usn/USN-1548-2
http://www.ubuntu.com/usn/USN-1548-1
http://www.securityfocus.com/bid/55277
http://www.mozilla.org/security/announce/2012/mfsa2012-62.html
http://rhn.redhat.com/errata/RHSA-2012-1211.html
http://rhn.redhat.com/errata/RHSA-2012-1210.html
http://lists.opensuse.org/opensuse-security-announce/2012-09/msg00014.html
http://lists.opensuse.org/opensuse-security-announce/2012-09/msg00011.html
http://lists.opensuse.org/opensuse-security-announce/2012-08/msg00028.html