CVE-2026-15576 (GCVE-0-2026-15576)

Vulnerability from cvelistv5 – Published: 2026-08-21 11:10 – Updated: 2026-08-21 11:53
VLAI
Title
Agent receiver accepts mTLS requests without a client certificate
Summary
Improper authentication in the agent receiver of Checkmk <2.5.0p10 allows an unauthenticated remote attacker to bypass mutual TLS client certificate verification of relay endpoints by supplying a fixed placeholder identity in the request URL, resulting in limited impact on integrity and availability. Only the Cloud, Ultimate and Ultimate MT editions are affected, as other editions do not expose relay endpoints.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-21 11:53 UTC
CWE
  • CWE-306 - Missing Authentication for Critical Function
Assigner
Checkmk CNA under the mitre root
CNA scorecard A 91/100 over 18 records in the last 180 days details
References
URL Tags
https://checkmk.com/werk/20174 vendor-advisory
Impacted products
Vendor Product Version CPE status
Checkmk GmbH Checkmk Affected: 2.5.0 , < 2.5.0p10 (semver)
    cpe:2.3:a:checkmk:checkmk:*:*:*:*:*:*:*:*
Create a notification for this product.
Credits
PS Positive Security GmbH
Show details on NVD website
To clipboard 

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