FM Certificates
By default, MKFM will not sign with a 512-bit certificate. It is recommended that you create your FM certificates using RSA 2048 instead of RSA512. For example:
ProtectServer | ctcert c -s0 -k -trsa -z512 -lfm |
ProtectServer 2 | ctcert c -s0 -k -trsa -z2048 -lfm |
MKFM now uses SHA-512 instead of SHA-1. To continue using a legacy 512-bit certificate for signing with a SHA-1 hash, you can use the -3 option of the MKFM command, although this is not recommended.
NOTE For best practice, create your FM certificates using RSA 2048.