CVE-2006-4409
The Online Certificate Status Protocol (OCSP) service in the Security Framework in Apple Mac OS X 10.4 through 10.4.8 retrieve certificate revocation lists (CRL) when an HTTP proxy is in use, which could cause the system to accept certificates that have been revoked.
Date published : 2006-11-30
http://lists.apple.com/archives/security-announce/2006/Nov/msg00001.html