[38821] in bugtraq
RE: TCP/IP implementations do not adequately validate ICMP error messages
daemon@ATHENA.MIT.EDU (David Schwartz)
Wed May 11 22:42:57 2005
From: "David Schwartz" <davids@webmaster.com>
To: <bugtraq@securityfocus.com>
Date: Tue, 10 May 2005 13:38:19 -0700
Message-ID: <MDEHLPKNGKAHNMBLJOLKKEDNDLAB.davids@webmaster.com>
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> 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
