Subject: [ASA-201707-13] irssi: denial of service

Arch Linux Security Advisory ASA-201707-13
==========================================

Severity: Critical
Date    : 2017-07-13
CVE-ID  : CVE-2017-10965 CVE-2017-10966
Package : irssi
Type    : denial of service
Remote  : Yes
Link    : https://security.archlinux.org/AVG-342

Summary
=======

The package irssi before version 1.0.4-1 is vulnerable to denial of
service including arbitrary code execution and denial of service.

Resolution
==========

Upgrade to 1.0.4-1.

# pacman -Syu "irssi>=1.0.4-1"

The problems have been fixed upstream in version 1.0.4.

Workaround
==========

None.

Description
===========

- CVE-2017-10965 (denial of service)

When receiving messages with invalid time stamps, Irssi would try to
dereference a NULL pointer. This requires control over the IRC server,
or a position of man-in-the-middle to be exploited.

- CVE-2017-10966 (arbitrary code execution)

While updating the internal nick list, Irssi may incorrectly use the
GHashTable interface and free the nick while updating it. This will
then result in use-after-free conditions on each access of the hash
table. Note that this should not happen with a conforming IRC server,
so it requires control over the IRC server or a position of man-in-the-
middle to be exploitable.

Impact
======

A remote attacker in position of man-in-the-middle or controlling the
IRC server might be able to crash or execute arbitrary code on an
affected host.

References
==========

https://github.com/irssi/irssi/commit/5e26325317c72a04c1610ad952974e206384d291
https://irssi.org/security/irssi_sa_2017_07.txt
https://security.archlinux.org/CVE-2017-10965
https://security.archlinux.org/CVE-2017-10966