CVE-2012-3732
Mail in Apple iOS before 6 uses an S/MIME message’s From address as the displayed sender address, which allows remote attackers to spoof signed content via an e-mail message in which the From field does not match the signer’s identity.
Date published : 2012-09-20
http://lists.apple.com/archives/security-announce/2012/Sep/msg00003.html