What the vulnerability does
01Description
The Perfmatters plugin for WordPress is vulnerable to arbitrary file deletion via path traversal in all versions up to, and including, 2.5.9.1. This is due to the `PMCS::action_handler()` method processing the `$_GET['delete']` parameter without any sanitization, authorization check, or nonce verification. The unsanitized filename is concatenated with the storage directory path and passed to `unlink()`. This makes it possible for authenticated attackers, with Subscriber-level access and above, to delete arbitrary files on the server by using `../` path traversal sequences, including `wp-config.php` which would force WordPress into the installation wizard and allow full site takeover.
Explanation of Vulnerability in Simple Terms
02Summary
Perfmatters versions up to 2.5.9.1 contain a path traversal vulnerability that allows authenticated users to modify or delete files on the server outside the intended directory. An attacker with low-level access can manipulate file paths to reach sensitive system files. This vulnerability requires user authentication but no additional interaction, making it a significant risk for sites with multiple user accounts.
What an attacker can do
03Attacker Capabilities
Modify or delete files on the server outside the intended directory.
Potential impact on your site
04Site Impact
Authenticated users can corrupt or delete critical site files, causing data loss or site malfunction.
Conditions required to exploit
05Prerequisites
Attacker must have a low-privilege user account on the site.
Key dates
06Disclosure timeline
April 3, 2026
CVE published
April 8, 2026
Record updated
