CVE-2021-27182: Altn MDaemon

High severity, CVSS 8.8. EPSS: 1.6% chance of exploitation in the next 30 days.

An issue was discovered in MDaemon before 20.0.4. There is an IFRAME injection vulnerability in Webmail (aka WorldClient). It can be exploited via an email message. It allows an attacker to perform 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.