RedHat: RHSA-2009:1453-01 Moderate Advisory: Pidgin DoS Vulnerabilities

Pidgin is an instant messaging program which can log in to multiple accounts on multiple instant messaging networks simultaneously. Info/Query (IQ) is an Extensible Messaging and Presence Protocol (XMPP) specific request-response mechanism.
A NULL pointer dereference flaw was found in the way the Pidgin XMPP protocol plug-in processes IQ error responses when trying to fetch a custom smiley. A remote client could send a specially-crafted IQ error response that would crash Pidgin. (CVE-2009-3085)
A NULL pointer dereference flaw was found in the way the Pidgin IRC protocol plug-in handles IRC topics. A malicious IRC server could send a specially-crafted IRC TOPIC message, which once received by Pidgin, would lead to a denial of service (Pidgin crash). (CVE-2009-2703)
It was discovered that, when connecting to certain, very old Jabber serversvia XMPP, Pidgin may ignore the "Require SSL/TLS" setting. In these situations, a non-encrypted connection is established rather than the connection failing, causing the user to believe they are using an encrypted connection when they are not, leading to sensitive information disclosure (session sniffing). (CVE-2009-3026)
A NULL pointer dereference flaw was found in the way the Pidgin MSN protocol plug-in handles improper MSNSLP invitations. A remote attacker could send a specially-crafted MSNSLP invitation request, which once accepted by a valid Pidgin user, would lead to a denial of service (Pidgin crash). (CVE-2009-3083)
These packages upgrade Pidgin to version 2.6.2. Refer to the Pidgin release notes for a full list of changes: http://developer.pidgin.im/wiki/ChangeLog
All Pidgin users should upgrade to these updated packages, which correct these issues. Pidgin must be restarted for this update to take effect.