RHSA-2016:1978 — Security Advisory

An update for python-twisted-web is now available for Red Hat Enterprise Linux 6 and Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Twisted is an event-based framework for internet applications. Twisted Web is a complete web server, aimed at hosting web applications using Twisted and Python, but fully able to serve static pages too.

Security Fix(es):

• It was discovered that python-twisted-web used the value of the Proxy header from HTTP requests to initialize the HTTP_PROXY environment variable for CGI scripts, which in turn was incorrectly used by certain HTTP client implementations to configure the proxy for outgoing HTTP requests. A remote attacker could possibly use this flaw to redirect HTTP requests performed by a CGI script to an attacker-controlled proxy via a malicious HTTP request. (CVE-2016-1000111)

Note: After this update, python-twisted-web will no longer pass the value of the Proxy request header to scripts via the HTTP_PROXY environment variable.

Red Hat would like to thank Scott Geary (VendHQ) for reporting this issue.