CVE-2026-15937: Checkmk GmbH Checkmk

Medium severity, CVSS 5.3. EPSS: 0.1% chance of exploitation in the next 30 days.

Improper certificate validation in Checkmk <2.5.0p10 allows a relay and a push agent that share the same UUID to reuse each other's mTLS certificate to authenticate against agent receiver endpoints in either direction, because the endpoints do not verify that the certificate was issued by their own root certificate.

Affected products

• Checkmk GmbH Checkmk: from 2.5.0, before 2.5.0p10 (fixed in 2.5.0p10)

Published 2026-09-04. Last modified 2026-09-08.