CVSS 4.0
9.4 criticalCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:HCVE-2026-121374 Arbitrary file write and code execution via excluded node roles in Kubernetes special agent
Critical (9.4) in checkmk gmbh checkmk. EPSS 0.4% estimated probability of exploitation activity in the next 30 days.
On this page
Argument injection in the Kubernetes special agent in Checkmk <2.5.0p19, <2.4.0p40, and 2.3.0 (EOL) allows a user with permission to edit rules in at least one folder to write files to arbitrary locations writable by the site user via crafted node roles in the "Exclude nodes based on their role" rule option, leading to code execution as the site user.
Severity
- EPSS
- 0.4% estimated probability of exploitation activity in the next 30 days; 33rd percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CWE
- CWE-88 Improper Neutralization of Argument Delimiters in a Command (Argument Injection)
- OWASP Top 10
- A05:2025 Injection
- Published
- Modified
- Assigned by
- Checkmk (CNA)
- NVD analysis
- Deferred: the NVD does not plan to analyze it
- Record from
- the NVD, synced
Ask an AI about this CVE
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Affected
- checkmk gmbh:checkmk
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| Checkmk GmbH Checkmk | from 2.5.0 before 2.5.0p19 |
| Checkmk GmbH Checkmk | from 2.4.0 before 2.4.0p40 |
| Checkmk GmbH Checkmk | 2.3.0 |
Attack patterns (CAPEC)
- CAPEC-41 Using Meta-characters in E-mail Headers to Inject Malicious Payloads Likelihood: High · Severity: High
- CAPEC-88 OS Command Injection Likelihood: High · Severity: High
- CAPEC-137 Parameter Injection Likelihood: Medium · Severity: Medium
- CAPEC-174 Flash Parameter Injection Likelihood: High · Severity: Medium
- CAPEC-460 HTTP Parameter Pollution (HPP) Severity: Medium
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.
History
- The NVD deferred its analysis
Changes since this site first stored the record. The same for every record: /api/public/changes.