Subject: [shara] SHARA: issue with path MTU discovery 'attack'

From: "Eric Vyncke (evyncke)" <[email-masked]>
Date: Fri, 13 Nov 2009 01:39:32 +0100

Mat

Thanks again for compiling the list of issues in your I-D.

One security issue which is missing is that a NAT'ed malovent user could send a 'ICMP packet too big, use MTU=100' which will be cached by the off-net server (think google.com or youtube.com) for _ALL_ subscribers behind the NAT. Which leads to a medium DoS against the remote server as well as on the NAT device itself (as it will have to handle many more packet/sec).

Hope this helps

-éric