CVE-2021-21660

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.

• CWE-79

• http://www.openwall.com/lists/oss-security/2021/05/25/3Mailing List, Third Party Advisory
• https://www.jenkins.io/security/advisory/2021-05-25/#SECURITY-2198Vendor Advisory
• https://www.whitesourcesoftware.com/vulnerability-database/CVE-2021-21660Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/05/25/3Mailing List, Third Party Advisory
• https://www.jenkins.io/security/advisory/2021-05-25/#SECURITY-2198Vendor Advisory
• https://www.whitesourcesoftware.com/vulnerability-database/CVE-2021-21660Third Party Advisory

Published

May 25, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
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