Requests (aka python-requests) before 2.3.0 allows remote servers to obtain sensitive information by reading the Proxy-Authorization header in a redirected request.
https://github.com/kennethreitz/requests/issues/1885
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=733108
http://www.mandriva.com/security/advisories?name=MDVSA-2015:133
http://www.debian.org/security/2015/dsa-3146
http://lists.opensuse.org/opensuse-updates/2016-01/msg00095.html