CVE-2021-35299: Zammad

High severity, CVSS 7.5. EPSS: 1.1% chance of exploitation in the next 30 days.

Incorrect Access Control in Zammad 1.0.x up to 4.0.0 allows attackers to obtain sensitive information via email connection configuration probing.

Affected products

• Zammad Zammad: from 1.0.0, up to and including 4.0.0

Published 2021-06-28. Last modified 2026-06-17.