A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to tamper with signed URLs by appending further data which allows bypass of signature verification.

Multiple improper neutralization of special elements of SQL commands vulnerabilities in FortiMail before 6.4.4 may allow a non-authenticated attacker to execute unauthorized code or commands via specifically crafted HTTP requests.

Multiple instances of incorrect calculation of buffer size in the Webmail and Administrative interface of FortiMail before 6.4.5 may allow an authenticated attacker with regular webmail access to trigger a buffer overflow and to possibly execute unauthorized code or commands via specifically crafted HTTP requests.