Image checksums
To verify the integrity of the firmware file, use a checksum tool to compute the firmware file’s MD5 checksum. Compare it with the checksum indicated by Fortinet. If the checksums match, the file is intact.
MD5 checksums for software releases are available from Fortinet Customer Service & Support:
VM Image integrity is also verified when the FortiWeb is booting up. the running OS will generate signatures and compare them with the signatures attached to the image. If the signatures do not match, the running OS will be shutdown.
To download the Customer Service & Support image checksum tool
After logging in to the website, in the menus at the top of the page, click Download, and then click Firmware Image Checksums.
Alternatively, near the bottom of the page, click the Firmware Image Checksums button. This button appears only if one or more of your devices has a current support contract. In the File Name field, enter the firmware image file name including its extension, then click Get Checksum Code.