Buffer overflow in QuickLook in Apple Mac OS X 10.5.8 and 10.6.x before 10.6.5 allows remote attackers to execute arbitrary code or cause a denial of service (application crash) via a crafted Microsoft Office document.
http://www.securitytracker.com/id?1024723
http://support.apple.com/kb/HT5004
http://support.apple.com/kb/HT4435
http://lists.apple.com/archives/security-announce/2010//Nov/msg00000.html
http://lists.apple.com/archives/Security-announce/2011//Oct/msg00006.html