CVE 2011-1428
Wee Enhanced Environment for Chat (aka WeeChat) 0.3.4 and earlier does not properly verify that the server hostname matches the domain name of the subject of an X.509 certificate, which allows man-in-the-middle attackers to spoof an SSL chat server via an arbitrary certificate, related to incorrect use of the GnuTLS API.
See the 
CVE page on Mitre.org
for more details.
