Vulnerability · Published Feb 19, 2026 · Assigned by Wordfence
CVE-2026-0561Shield Security <= 21.0.8 - Unauthenticated Reflected Cross-Site Scripting via 'message' Parameter
Medium 6.1
In plain English
A medium-severity cross-site scripting in Shield: Blocks Bots, Protects Users, and Prevents Security Breaches from paultgoodchild. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 52% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei.
Official description
The Shield Security plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'message' parameter in all versions up to, and including, 21.0.8 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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| paultgoodchild | Shield: Blocks Bots, Protects Users, and Prevents Security Breaches | 0 – through 21.0.8 |
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
References
- https://www.wordfence.com/threat-intel/vulnerabilities/id/cb49eb5f-c1ff-4440-8b53-c2515e65da27?source=cve
- https://research.cleantalk.org/cve-2026-0561
- https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3439494%40wp-simple-firewall&new=3439494%40wp-simple-firewall&sfp_email=&sfph_mail=