CVE-2021-28001: Textpattern

Medium severity, CVSS 5.4. EPSS: 1% chance of exploitation in the next 30 days.

A cross-site scripting vulnerability was discovered in the Comments parameter in Textpattern CMS 4.8.4 which allows remote attackers to execute arbitrary code via a crafted payload entered into the URL field. The vulnerability is triggered by users visiting https://site.com/articles/welcome-to-your-site#comments-head.

Affected products

• Textpattern Textpattern: version 4.8.4 only

Published 2021-08-19. Last modified 2026-06-17.