Fortigate Firmware May 2026

If you have two FortiGates in an Active-Passive HA cluster, do not upgrade them separately. Use Uninterruptible Upgrade:

Warning: Ensure session synchronization is working before starting (diagnose sys ha status). fortigate firmware

Always hash the downloaded firmware file (out suffix) against the MD5/SHA256 checksum provided on the support portal. A single corrupted bit can corrupt the flash memory. If you have two FortiGates in an Active-Passive

Do not confuse firmware with security definitions. You can have the latest definitions on an

You can have the latest definitions on an old firmware, but you cannot patch OS-level CVEs with definitions.

Fortinet releases firmware in three main tracks, each serving a different purpose: