CVE-2014-9772

Versions of validator prior to 2.0.0 contained an xss filter method that is affected by several filter bypasses. This may result in a cross-site scripting vulnerability.

Proof of Concept

The xss() function removes the word "javascript" when contained inside an attribute.

However, it does not properly handle cases where characters have been hex-encoded.

As a result, it is possible to build an input that bypasses the filter but which the browser will accept as valid JavaScript.

For example:
<a href="jav&#x61;script:...">abc</a>
will render as:
<a href="javascript:...">abc</a>

Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.

CVE-2014-9772 has a CVSS score of 6.1 (Medium). The vector is network-reachable, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.0.0); upgrading removes the vulnerable code path.

Kodem intelligence

The package author has decided to remove the xss filter functionality in the latest version of this module. If this feature is not currently being used, you are not affected by the vulnerability. If it is being used, updating to the latest version of the module will break your application.

In order for affected users to mitigate this vulnerability, it is necessary to use an alternative package that provides similar functionality.

1. What is CVE-2014-9772? CVE-2014-9772 is a medium-severity cross-site scripting (XSS) vulnerability in validator (npm), affecting versions < 2.0.0. It is fixed in 2.0.0. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
2. How severe is CVE-2014-9772? CVE-2014-9772 has a CVSS score of 6.1 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of validator are affected by CVE-2014-9772? validator (npm) versions < 2.0.0 is affected.
4. Is there a fix for CVE-2014-9772? Yes. CVE-2014-9772 is fixed in 2.0.0. Upgrade to this version or later.
5. Is CVE-2014-9772 exploitable, and should I be worried? Whether CVE-2014-9772 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2014-9772 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2014-9772? Upgrade validator to 2.0.0 or later.