Pidgin is an instant messaging program which can log in to multiple accounts on multiple instant messaging networks simultaneously. The AOL Open System for Communication in Realtime protocol is used by the AOL ICQ and AIM instant messaging systems. An invalid pointer dereference bug was found in the way the Pidgin OSCAR protocol implementation processed lists of contacts. A remote attacker could send a specially-crafted contact list to a user running Pidgin, causing Pidgin to crash. These packages upgrade Pidgin to version 2.6.3. Pidgin must be restarted for this update to take effect.