linksys router + irc DoS

2006-03-05T00:00:00
ID SECURITYVULNS:DOC:11692
Type securityvulns
Reporter Securityvulns
Modified 2006-03-05T00:00:00

Description

Bug:

Certain Linksys (and possibly Netgear) routers will reset an IRC connection when a malformed DCC request is received. In fact, it doesn't even have to be a proper DCC request, the flaw can be triggered simply by sending the following string such that it is received by the user in some way.

DCC SEND "foo" 0 0 0

Presumably this is due to by the masquerading code that enables DCCs to work correctly behind a NAT.

Workaround:

Connect to a non-standard port and the masquerading code won't recognize it as an IRC connection.

Verified on:

Linskys WRT54G

p.s. i am lazy and am not sending this to linksys. someone else can if they feel inclined to do so. also i didn't find the problem; the workaround was trivial.

-- Regards, Cade Cairns