CVE-2026-15937mediumCWE-295

CVE-2026-15937: medium-severity vulnerability in Checkmk

Agent receiver certificate confusion allows authentication with a certificate issued for another endpoint

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 5.3epss 0.2%
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
Affected products
Checkmk GmbH · Checkmk
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