PT-2026-26494 · Packagist · Johnbillion/Query-Monitor

Published

2026-03-19

·

Updated

2026-03-19

·

CVE-2026-4267

CVSS v3.1

6.1

Medium

AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Impact

The Query Monitor plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the $ SERVER['REQUEST URI'] parameter in all versions up to, and including, 3.20.3 due to insufficient output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick an Administrator-level user into performing an action such as clicking on a link.
On admin requests, the plugin reads user controlled data from $ SERVER['REQUEST URI'] and stores it in the request field, then renders request, matched query, and query string through format url(). If the attacker supplied string does not contain &, format url() returns it without HTML escaping, which allows injected HTML or JavaScript from the request target to be inserted directly into the page inside a <code> element and executed in the victim's browser.

Patches

This issue has been patched in Query Monitor 3.20.4.

Credits

Many thanks to Dmitrii Ignatyev at CleanTalk for responsibly disclosing this vulnerability.

How can I report a security bug?

You can submit a private security vulnerability report to Query Monitor via the Security tab on the GitHub repo. The GitHub Security Advisory process facilitates private collaboration on security issues. You'll receive credit for a valid report and a CVE if necessary.

Fix

XSS

Weakness Enumeration

CWE-80

Related Identifiers

CVE-2026-4267
GHSA-2XR4-CHCF-VMVF

Affected Products

Johnbillion/Query-Monitor