CVE-2021-35303: Zammad

Medium severity, CVSS 6.1. EPSS: 0.8% chance of exploitation in the next 30 days.

Cross Site Scripting (XSS) in Zammad 1.0.x up to 4.0.0 allows remote attackers to execute arbitrary web script or HTML via the User Avatar attribute.

Affected products

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

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