FortiMail - Unauthenticated encryption in IBE leads to email plaintext recovery


A missing cryptographic step in FortiMail IBE may allow an unauthenticated attacker who intercepts the encrypted messages to manipulate them in such a way that makes the tampering and the recovery of the plaintexts possible.

Affected Products

FortiMail version 6.4.4 and below.
FortiMail version 6.2.6 and below.


Please upgrade to FortiMail version 7.0.0 or above


Internally discovered and reported by Giuseppe Cocomazzi of Fortinet PSIRT.