The irc_msg_who function in msgs.c in the IRC protocol plugin in libpurple 2.8.0 through 2.9.0 in Pidgin before 2.10.0 does not properly validate characters in nicknames, which allows user-assisted remote attackers to cause a denial of service (NULL pointer dereference and application crash) via a crafted nickname that is not properly handled in a WHO response. Per: http://cwe.mitre.org/data/definitions/476.html
'CWE-476: NULL Pointer Dereference'
Publication date: Mon, 29 Aug 2011 22:55:00 +0000