SMTP Auth Failure - too many brute force

[kkriss]

Hi

i'm using Fortimail 400e, how to prevent to brute force attack to smtp to port 25?

Maybe connect fortigate between WAN and fortimail but how to configure fortigate to prevent brute force attack to smtp?

Now i'm using juniper netscreen just to lock or unlock ports, but i can change it to FG.

[Carl_Windsor_FTNT]

This can be done on FML.  See page 298 of the CLI Guide

system security authserver Use this command to modify the tracking functions used to prevent password guessing attempts. The sender IP addresses in the exempt list will bypass the security checking.

Syntax:

config system security authserver
    config exempt-list
      edit auth_exempt_id
          set sender-ip-mask
      end
    set status (disable | enable | monitor-only)
end