A vulnerability, a security issue, and a weakness have been reported in Pidgin, which can be exploited by malicious people to disclose sensitive information, cause a DoS (Denial of Service), or potentially compromise a user's system.

1) An error in the "msn_slplink_process_msg()" function when processing MSN SLP messages can be exploited to corrupt memory.

Successful exploitation may allow execution of arbitrary code.

The vulnerability is reported in versions 2.5.8 and prior. Other versions may also be affected.

2) The application connects to Jabberd servers that are not fully compliant with the XMPP specifications without encryption, even if the "Require SSL/TLS" setting is configured. This can be exploited to potentially disclose sensitive information transmitted during an XMPP session.

The security issue is reported in versions prior to 2.6.0.

3) An error when processing links received via the Yahoo Messenger protocol can be exploited to crash the application.

The weakness is reported in version 2.6.0.

Solution
Update to version 2.6.1.

Provided and/or discovered by
1) Federico Muttis, Core Security Technologies
2) Reported by bugdave in a Pidgin bug report.
3) Reported by adk in a Pidgin bug report.

Changelog
Further details available to Secunia VIM customers

Original Advisory
Pidgin:
http://www.pidgin.im/news/security/?id=34
http://www.pidgin.im/news/security/?id=35
http://www.pidgin.im/news/security/?id=36

Core Security Technologies:
http://www.coresecurity.com/content/libpurple-arbitrary-write

Pidgin Trac:
http://developer.pidgin.im/ticket/8131
http://developer.pidgin.im/ticket/9946

Deep Links
Links available to Secunia VIM customers