Query Monitor <= 3.20.3 - Reflected Cross-Site Scripting via Request URI
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-79.
Summary
The Query Monitor – The developer tools panel for WordPress 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 input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| johnbillion | Query Monitor | up to 3.20.3 | — | No fix listed | CNA |
| — | johnbillion/query-monitor (Packagist) | before 3.20.4 | 3.20.4 | Patch available | GHSA-2xr4-chcf-vmvf |
- Query Monitor Vendorjohnbillion Affected up to 3.20.3 Fixed in — No fix listed CNA
- johnbillion/query-monitor (Packagist) Vendor— Affected before 3.20.4 Fixed in 3.20.4 Patch available GHSA-2xr4-chcf-vmvf
Remediation
- Fix · GHSA-2xr4-chcf-vmvf johnbillion/query-monitor (Packagist) Fixed in 3.20.4 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-4267
- 2026-10-03 Alias added: GHSA-2xr4-chcf-vmvf
References
Other 7
- https://www.wordfence.com/threat-intel/vulnerabilities/id/0b75cad9-9f76-4839-8eb2-40d84662846d?source=cve
- https://plugins.trac.wordpress.org/browser/query-monitor/tags/3.20.2/output/html/request.php#L60
- https://plugins.trac.wordpress.org/browser/query-monitor/tags/3.20.2/output/html/request.php#L70
- https://plugins.trac.wordpress.org/changeset/3486705/query-monitor
- https://research.cleantalk.org/cve-2026-4267/
- https://github.com/johnbillion/query-monitor/security/advisories/GHSA-2xr4-chcf-vmvf
- https://github.com/johnbillion/query-monitor
More johnbillion vulnerabilities
- TI-2024-19052 WP Crontrol possible RCE when combined with a pre-condition CVSS 3.1HIGH 8.2
- TI-2025-07942 WP Crontrol - 1.17.0 - 1.19.1 - Authenticated (Administrator+) Blind Server-Side Request Forgery CVSS 3.1MEDIUM 5.9
Sources
- CVE-2026-4267 · CVE Program
- CVE-2026-4267 · NVD
- FIRST EPSS
- GHSA-2xr4-chcf-vmvf · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences