First published: Fri Jul 08 2016(Updated: )
Dominic Scheirlinck of VendHQ reports: Many software projects and vendors have implemented support for the “Proxy” request header in their respective CGI implementations and languages by creating the “HTTP_PROXY” environmental variable based on the header value. When this variable is used (in many cases automatically by various HTTP client libraries) any outgoing requests generated in turn from the attackers original request can be redirected to an attacker controlled proxy. This allows attackers to view potentially sensitive information, reply with malformed data, or to hold connections open causing a potential denial of service. The Tomcat server contains support for CGI. If passed a “Proxy” header in the request CGIServlet will automatically populate the HTTP_PROXY environmental variable with whatever user supplied value is present.
Affected Software | Affected Version | How to fix |
---|---|---|
Tomcat |
Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.
The severity of REDHAT-BUG-1353809 is considered high due to potential exploits involving the misuse of the HTTP_PROXY environment variable.
To fix REDHAT-BUG-1353809, ensure that your Apache Tomcat configuration properly validates and sanitizes input from the Proxy request header.
REDHAT-BUG-1353809 affects various versions of Apache Tomcat that process the Proxy request header.
Exploiting REDHAT-BUG-1353809 can enable attackers to conduct man-in-the-middle attacks or access sensitive data through misconfigured proxies.
A temporary workaround for REDHAT-BUG-1353809 includes disabling the handling of the Proxy request header until a patch is applied.