Root escalation via site-controlled omd payload execution
Published Apr 7, 2026 · Updated Apr 7, 2026
Local privilege escalation in affected Checkmk 2.2.0, 2.3.0, 2.4.0, and 2.5.0 beta releases allows site users to gain root access. Root-run omd selects executable content from the site-controlled version directory and processes a planted payload with root privileges. Exploitation requires write access to a site's context and a later root invocation of an affected omd command; success compromises the host and its other sites.
Summary
What happened
Local privilege escalation in affected Checkmk 2.2.0, 2.3.0, 2.4.0, and 2.5.0 beta releases allows site users to gain root access. Root-run omd selects executable content from the site-controlled version directory and processes a planted payload with root privileges. Exploitation requires write access to a site's context and a later root invocation of an affected omd command; success compromises the host and its other sites.
The record
- CVE
- CVE-2025-39666
- Published
- Apr 7, 2026
- Updated
- Apr 7, 2026
- Vendor
- Checkmk GmbH
- Product
- Checkmk
- Classifications
- CWE-426, CWE-829, CAPEC-17, CAPEC-471, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 7, 2026CVE publishedPublication date reported by the CVE source.
- Apr 7, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2.2.0
- Affected versionversion=2.3.0 <2.3.0p46
- Affected versionversion=2.4.0 <2.4.0p25
- Affected versionversion=2.5.0b1 <2.5.0b3
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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