CVE-2026-2859 (GCVE-0-2026-2859)

Vulnerability from cvelistv5 – Published: 2026-03-13 09:40 – Updated: 2026-03-13 15:48
VLAI?
Title
Unauthenticated Host Enumeration via Observable Response Discrepancy on Deploy Agent Endpoint
Summary
Improper permission enforcement in Checkmk versions 2.4.0 before 2.4.0p23, 2.3.0 before 2.3.0p43, and 2.2.0 (EOL) allows unauthenticated users to enumerate existing hosts by observing different HTTP response codes in deploy_agent endpoint, which could lead to information disclosure.
Severity ?
6.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-204 - Observable Response Discrepancy
Assigner
References
Impacted products
Vendor Product Version
Checkmk GmbH Checkmk Affected: 2.4.0 , < 2.4.0p23 (semver)
Affected: 2.3.0 , < 2.3.0p43 (semver)
Affected: 2.2.0 (semver)
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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