Originally posted here by w-mellon
I had read some time ago on the securityfocus website about certain hardware equipment vulnerabilities in the tcp/ip stack concerning port 0 (old code in use on equipment could reset by port 0 destination port packet). Check the website for past bugtraps on this, may provide something useful.
Something like this?

Check Point FireWall-1 UDP Port 0 DoS

That is a bit old though...