CVE-2021-31866: Debian Linux

Medium severity, CVSS 5.3. EPSS: 1.2% chance of exploitation in the next 30 days.

Redmine before 4.0.9 and 4.1.x before 4.1.3 allows an attacker to learn the values of internal authentication keys by observing timing differences in string comparison operations within SysController and MailHandlerController.

Affected products

• Debian Debian Linux: version 9.0 only
• Redmine Redmine: before 4.0.9 (fixed in 4.0.9); from 4.1.0, before 4.1.3 (fixed in 4.1.3)

Published 2021-04-28. Last modified 2026-06-17.