CVE-2010-1637
The Mail Fetch plugin in SquirrelMail 1.4.20 and earlier allows remote authenticated users to bypass firewall restrictions and use SquirrelMail as a proxy to scan internal networks via a modified POP3 port number.
Date published : 2010-06-22
http://lists.apple.com/archives/security-announce/2012/Feb/msg00000.html