Security Advisory

ZF2012-04: Potential Proxy Injection Vulnerabilities in Multiple Zend Framework 2 Components

Zend\Session\Validator\RemoteAddr and Zend\View\Helper\ServerUrl were found to be improperly parsing HTTP headers for proxy information, which could potentially allow an attacker to spoof a proxied IP or host name.

In Zend\Session\Validator\RemoteAddr, if the client is behind a proxy server, the detection of the proxy URL was incorrect, and could lead to invalid results on subsequent lookups.

In Zend\View\Helper\ServerUrl, if the server lives behind a proxy, the helper would always generate a URL based on the proxy host, regardless of whether or not this was desired; additionally, it did not take into account the proxy port or protocol, if provided.

Action Taken

A new class, Zend\Http\PhpEnvironment\RemoteAddress, was developed to provide reusable code surrounding the detection of a client IP via proxy headers, and Zend\Session\Validator\RemoteAddr was refactored to consume this class. This code:

The ServerUrl view helper was modified as follows:

This patch has been applied starting in versions 2.0.5 of Zend Framework, as well as to the 2.1 development branch.

Recommendations

If you are using any of the components listed, we recommend upgrading to 2.0.5 or greater.

Other Information

Acknowledgments

The Zend Framework team thanks the following for identifying the issues and working with us to help protect its users:

  • Fabien Potencier

Reporting Potential Security Issues

If you have encountered a potential security vulnerability in Zend Framework, please report it to us at zf-security@zend.com. We will work with you to verify the vulnerability and patch it.

When reporting issues, please provide the following information:

  • Component(s) affected
  • A description indicating how to reproduce the issue
  • A summary of the security vulnerability and impact

We request that you contact us via the email address above and give the project contributors a chance to resolve the vulnerability and issue a new release prior to any public exposure; this helps protect Zend Framework users and provides them with a chance to upgrade and/or update in order to protect their applications.

For sensitive email communications, please use our PGP key.

Policy

Zend Framework takes security seriously. If we verify a reported security vulnerability, our policy is:

  • We will patch the current release branch, as well as the immediate prior minor release branch.
  • After patching the release branches, we will immediately issue new security fix releases for each patched release branch.
  • A security advisory will be released on the Zend Framework site detailing the vulnerability, as well as recommendations for end-users to protect themselves. Security advisories will be listed at http://framework.zend.com/security/advisories, as well as via a feed (which is also present in the website head for easy feed discovery)

back to advisories