libpurple in Finch in Pidgin before 2.6.6, when an XMPP multi-user chat (MUC) room is used, does not properly parse nicknames containing <br> sequences, which allows remote attackers to cause a denial of service (application crash) via a crafted nickname.
https://rhn.redhat.com/errata/RHSA-2010-0115.html
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A18230
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11485
https://exchange.xforce.ibmcloud.com/vulnerabilities/56399
https://bugzilla.redhat.com/show_bug.cgi?id=565786
http://www.vupen.com/english/advisories/2010/1020
http://www.vupen.com/english/advisories/2010/0914
http://www.vupen.com/english/advisories/2010/0413
http://www.ubuntu.com/usn/USN-902-1
http://www.securityfocus.com/bid/38294
http://www.mandriva.com/security/advisories?name=MDVSA-2010:085
http://www.mandriva.com/security/advisories?name=MDVSA-2010:041
http://www.debian.org/security/2010/dsa-2038
http://secunia.com/advisories/39509
http://secunia.com/advisories/38915
http://secunia.com/advisories/38712
http://secunia.com/advisories/38658
http://secunia.com/advisories/38640
http://secunia.com/advisories/38563
http://pidgin.im/news/security/?id=44
http://lists.opensuse.org/opensuse-security-announce/2010-03/msg00004.html
http://lists.fedoraproject.org/pipermail/package-announce/2010-February/035409.html
http://lists.fedoraproject.org/pipermail/package-announce/2010-February/035347.html
http://lists.fedoraproject.org/pipermail/package-announce/2010-February/035332.html