The Python client in Apache Qpid before 2.2 does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate.
https://issues.apache.org/jira/browse/QPID-4918
http://svn.apache.org/viewvc?view=revision&revision=1460013
http://secunia.com/advisories/54137
http://secunia.com/advisories/53968
http://rhn.redhat.com/errata/RHSA-2013-1024.html
http://qpid.apache.org/releases/qpid-0.22/release-notes.html