VMWare Zimbra Mailer Release 8.6.0.GA Replay Attack

Hi@all, VMWare Zimbra Mailer Release 8.6.0.GA, latest patch and prior versions with DKIM implementation are vulnerable to longterm Mail Replay attacks. If the expiration header is not set, the signature never expires. This means, that the e-mail, perhaps catched while performing a man in the midd...