CVE-2026-56022: Webmin

Medium severity, CVSS 5.3. EPSS: 0.6% chance of exploitation in the next 30 days.

Webmin accepts basic authentication without session cookies when an attacker provides the 'User-Agent: webmin' header, allowing bypass of additional MFA requirements. Fixed in 2.640.

Affected products

• Webmin Webmin: before 2.640 (fixed in 2.640)

Published 2026-06-18. Last modified 2026-08-11.