FortiMail - Improper cryptographic operations in cookie encryption potentially prone to forgery
The combination of various cryptographic issues in the session management of FortiMail, including the encryption construction of the session cookie, may allow a remote attacker already in possession of a cookie to possibly reveal and alter or forge its content, thereby escalating privileges.
FortiMail 6.4.4 and below.
FortiMail 6.2.6 and below.
Upgrade to FortiMail 7.0.0.
Upgrade to FortiMail 6.4.5.