What the vulnerability does
01Description
The AddFunc Head & Footer Code plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the `aFhfc_head_code`, `aFhfc_body_code`, and `aFhfc_footer_code` post meta values in all versions up to, and including, 2.3. This is due to the plugin outputting these meta values without any sanitization or escaping. While the plugin restricts its own metabox and save handler to administrators via `current_user_can('manage_options')`, it does not use `register_meta()` with an `auth_callback` to protect these meta keys. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts via the WordPress Custom Fields interface that execute when an administrator previews or views the post.
Explanation of Vulnerability in Simple Terms
02Summary
AddFunc Head & Footer Code versions 2.3 and earlier contain a stored cross-site scripting (XSS) vulnerability. An authenticated user with low privileges can inject malicious scripts into the plugin's settings. These scripts execute in the browsers of other site users, potentially compromising their sessions or stealing sensitive data. The vulnerability affects all users of the site.
What an attacker can do
03Attacker Capabilities
Inject malicious scripts that execute in other users' browsers when they view affected pages.
Potential impact on your site
04Site Impact
Any authenticated user can inject code affecting all site visitors; compromises user sessions and data security.
Conditions required to exploit
05Prerequisites
Attacker must have a low-privilege authenticated account on the site.
Key dates
06Disclosure timeline
April 10, 2026
CVE published
April 10, 2026
Record updated
