All users of Apple's Quicktime video facility should update to 7.1

Apple QuickTime Vulnerabilities - Update to v7.1
http://www.us-cert.gov/cas/techalerts/TA06-132B.html

Apple QuickTime contains multiple vulnerabilities. Exploitation of these vulnerabilities could allow a remote attacker to execute arbitrary code or cause a denial-of-service condition. An attacker may be able to exploit this vulnerability by persuading a user to access a specially crafted file with a web browser. Disabling QuickTime in your web browser will defend against this attack vector.