RE: TCP/IP implementations do not adequately validate ICMP error messages

["David Schwartz" <davids () webmaster com>]

> when I add the following rule to iptables, the linux server (Kernel
> 2.4.29-grsec) is no longer vulnerable to the DOS:
> iptables -I INPUT 1 -p icmp -j DROP
>
> I am interested in knowing if this work around makes any sense. Please
> keep me informed about this vulnerability.

        This breaks PMTU detection. ICMP is a host requirement, it is not optional.

        DS