CVE-2021-21660: Jenkins Markdown Formatter

Medium severity, CVSS 5.4. EPSS: 1.1% chance of exploitation in the next 30 days.

Jenkins Markdown Formatter Plugin 0.1.0 and earlier does not sanitize crafted link target URLs, resulting in a stored cross-site scripting (XSS) vulnerability exploitable by attackers with the ability to edit any description rendered using the configured markup formatter.

Affected products

• Jenkins Markdown Formatter: up to and including 0.1.0

Published 2021-05-25. Last modified 2026-06-17.