CVE-2021-27180: Altn MDaemon

Medium severity, CVSS 6.1. EPSS: 0.9% chance of exploitation in the next 30 days.

An issue was discovered in MDaemon before 20.0.4. There is Reflected XSS in Webmail (aka WorldClient). It can be exploited via a GET request. It allows performing any action with the privileges of the attacked user.

Affected products

• Altn MDaemon: before 20.0.4 (fixed in 20.0.4)

Published 2021-04-14. Last modified 2026-06-17.