CRLF injection vulnerability in the HTTPConnection.putheader function in urllib2 and urllib in CPython (aka Python) before 2.7.10 and 3.x before 3.4.4 allows remote attackers to inject arbitrary HTTP headers via CRLF sequences in a URL.

Affected: Ubuntu:14.04:LTS: python2.7, Ubuntu:14.04:LTS: python3.4, Ubuntu:16.04:LTS: python2.7, Ubuntu:16.04:LTS: python3.5

It was discovered that the smtplib library in Python did not return an error when StartTLS fails. A remote attacker could possibly use this to expose sensitive information. (CVE-2016-0772)

Rémi Rampin discovered that Python would not protect CGI applications from contents of the HTTP_PROXY environment variable when based on the contents of the Proxy header from HTTP requests. A remote attacker could possibly use this to cause a CGI application to redirect outgoing HTTP requests. (CVE-2016-1000110)

Insu Yun discovered an integer overflow in the zipimporter module in Python that could lead to a heap-based overflow. An attacker could use this to craft a special zip file that when read by Python could possibly execute arbitrary code. (CVE-2016-5636)

Guido Vranken discovered that the urllib modules in Python did not properly handle carriage return line feed (CRLF) in headers. A remote attacker could use this to craft URLs that inject arbitrary HTTP headers. This issue only affected Ubuntu 12.04 LTS and Ubuntu 14.04 LTS. (CVE-2016-5699)