Executive Summary

The Allow HTML in Category Descriptions plugin for WordPress has a Stored Cross-Site Scripting (XSS) vulnerability in all versions up to and including 1.2.4.

This vulnerability arises because the plugin removes the `wp_kses_data` output filter for certain fields (term_description, link_description, link_notes, and user_description) without verifying user permissions.

As a result, authenticated users with administrator-level access or higher can inject malicious scripts into category descriptions.

These scripts execute whenever any user views a page displaying the affected category description.

This issue only affects multi-site WordPress installations or installations where the unfiltered_html capability has been disabled.

Useful 0 Not Useful 0

Impact Analysis

This vulnerability can allow attackers with administrator-level access to inject arbitrary web scripts into category descriptions.

When other users visit pages displaying these category descriptions, the malicious scripts will execute in their browsers.

This can lead to unauthorized actions such as stealing user credentials, session hijacking, defacement, or spreading malware.

Because the attack requires high-level privileges, the risk is somewhat limited to compromised or malicious administrators, but the impact on site users can be significant.

Useful 0 Not Useful 0

Compliance Impact

I don't know

Useful 0 Not Useful 0

Detection Guidance

I don't know

Useful 0 Not Useful 0

Mitigation Strategies

To mitigate this vulnerability, you should update or remove the Allow HTML in Category Descriptions plugin if it is installed and running a version up to and including 1.2.4.

Additionally, ensure that only trusted users have administrator-level access, as the vulnerability requires authenticated attackers with administrator privileges.

If updating is not immediately possible, consider disabling the plugin or restricting access to category descriptions to prevent injection of arbitrary scripts.

Also, verify that your WordPress installation is either not multi-site or that the unfiltered_html capability is enabled for trusted users, as the vulnerability only affects multi-site installations or those with unfiltered_html disabled.

Useful 0 Not Useful 0