The OpenGL implementation in Apple Mac OS X before 10.7.3 does not properly perform OpenGL Shading Language (aka GLSL) compilation, which allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted program.
http://support.apple.com/kb/HT5503
http://support.apple.com/kb/HT5130
http://lists.apple.com/archives/security-announce/2012/Sep/msg00003.html
http://lists.apple.com/archives/security-announce/2012/Feb/msg00000.html