Security Advisory

ZF2012-03: Potential XSS Vectors in Multiple Zend Framework 2 Components

Zend\Debug, Zend\Feed\PubSubHubbub, Zend\Log\Formatter\Xml, Zend\Tag\Cloud\Decorator, Zend\Uri, Zend\View\Helper\HeadStyle, Zend\View\Helper\Navigation\Sitemap, and Zend\View\Helper\Placeholder\Container\AbstractStandalone were not using Zend\Escaper when escaping HTML, HTML attributes, and/or URLs. While most were performing some escaping, because they were not using context-appropriate escaping mechanisms, they could potentially be exploited to perform Cross Site Scripting (XSS) attacks.

Action Taken

Each component and/or class was evaluated to determine which context-appropriate escaping mechanism should be used, and the appropriate method from Zend\Escaper\Escaper was then used. In most cases, this also involved composing the Escaper class as an injectible dependency.

In the case of Zend\Tag\Cloud\Decorator, the HtmlCloud and HtmlTag decorators were found to lack validation of user-provided HTML element and attribute names. Logic was added to validate these and raise an exception if invalid.

This patch has been applied starting in versions 2.0.1 of Zend Framework, as well as to the 2.1 development branch.


If you are using any of the components listed, we recommend upgrading to 2.0.1 or greater.

Other Information


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

Reporting Potential Security Issues

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

When reporting issues, please provide the following information:

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.


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

Released Thu, 20 September 2012 16:00:00 -0500.

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