Debian: DSA 099-1 Critical: XChat Remote Session Hijacking

Debian Security Advisory DSA 099-1 security@debian.org
Debian -- Security Information Martin Schulze
January 12th, 2002

Package : XChat
Vulnerability : IRC session hijacking
Problem-Type : remote vulnerability
Debian-specific: no

zen-parse found a vulnerability in the XChat IRC client that allows an
attacker to take over the users IRC session.

It is possible to trick XChat IRC clients into sending arbitrary
commands to the IRC server they are on, potentially allowing social
engineering attacks, channel takeovers, and denial of service. This
problem exists in versions 1.4.2 and 1.4.3. Later versions of XChat
are vulnerable as well, but this behaviour is controlled by the
configuration variable »percascii«, which defaults to 0. If it is set
to 1 then the problem becomes apparent in 1.6/1.8 a swell.

This problem has been fixed in upstream version 1.8.7 and in version
1.4.3-1 for the current stable Debian release (2.2) with a patch
provid...