A denial of service vulnerability exists in the handling of the MXIT protocol in Pidgin. Specially crafted MXIT data sent from the server could potentially result in an out-of-bounds read. A malicious server or man-in-the-middle attacker can send invalid data to trigger this vulnerability.
https://security.gentoo.org/glsa/201701-38
http://www.ubuntu.com/usn/USN-3031-1
http://www.talosintelligence.com/reports/TALOS-2016-0138/
http://www.securityfocus.com/bid/91335