core/nicklist.c in Irssi before 0.8.15 allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via vectors related to an attempted fuzzy nick match at the instant that a victim leaves a channel.
https://exchange.xforce.ibmcloud.com/vulnerabilities/57791
http://www.vupen.com/english/advisories/2010/1110
http://www.vupen.com/english/advisories/2010/1107
http://www.vupen.com/english/advisories/2010/0987
http://www.vupen.com/english/advisories/2010/0856
http://www.ubuntu.com/usn/USN-929-1
http://svn.irssi.org/cgi-bin/viewvc.cgi/irssi/trunk/src/core/nicklist.c?root=irssi&r1=4922&r2=5126
http://slackware.com/security/viewer.php?l=slackware-security&y=2010&m=slackware-security.497301
http://securitytracker.com/id?1023845
http://secunia.com/advisories/39797
http://secunia.com/advisories/39620
http://secunia.com/advisories/39365
http://marc.info/?l=oss-security&m=127119240204394&w=2
http://marc.info/?l=oss-security&m=127115784314970&w=2
http://marc.info/?l=oss-security&m=127111071631857&w=2
http://marc.info/?l=oss-security&m=127110132019166&w=2
http://marc.info/?l=oss-security&m=127098845125270&w=2
http://lists.opensuse.org/opensuse-security-announce/2010-05/msg00001.html
http://lists.fedoraproject.org/pipermail/package-announce/2010-May/041054.html