CVE-2010-4554
functions/page_header.php in SquirrelMail 1.4.21 and earlier does not prevent page rendering inside a frame in a third-party HTML document, which makes it easier for remote attackers to conduct clickjacking attacks via a crafted web site.
Date published : 2011-07-14
http://lists.apple.com/archives/security-announce/2012/Feb/msg00000.html