directconn.c in the MSN protocol plugin in libpurple 2.7.6 through 2.7.8 in Pidgin before 2.7.9 allows remote authenticated users to cause a denial of service (NULL pointer dereference and application crash) via a short p2pv2 packet in a DirectConnect (aka direct connection) session.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A18461
https://bugzilla.redhat.com/show_bug.cgi?id=665421
http://www.vupen.com/english/advisories/2011/0076
http://www.vupen.com/english/advisories/2011/0054
http://www.vupen.com/english/advisories/2011/0028
http://www.securityfocus.com/bid/45581
http://www.pidgin.im/news/security/?id=49
http://www.openwall.com/lists/oss-security/2010/12/31/5
http://www.openwall.com/lists/oss-security/2010/12/27/1
http://www.mandriva.com/security/advisories?name=MDVSA-2010:259
http://secunia.com/advisories/42877
http://secunia.com/advisories/42824
http://secunia.com/advisories/42732
http://pidgin.im/pipermail/support/2010-December/009251.html
http://lists.opensuse.org/opensuse-security-announce/2011-01/msg00003.html
http://lists.fedoraproject.org/pipermail/package-announce/2011-January/052905.html
http://lists.fedoraproject.org/pipermail/package-announce/2011-January/052862.html
http://developer.pidgin.im/viewmtn/revision/info/aaa07bde3c51d3684391ae6ed86b6dbaeab5d031