Is there a public exploit for CVE-2026-121374?

No public exploit for CVE-2026-121374 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-121374?

CVE-2026-121374 scores CVSS 9.4 (v4.0), rated critical.

What does CVE-2026-121374 affect?

CVE-2026-121374 affects Checkmk GmbH Checkmk.

9.4 Critical

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…

CVE-2026-121374

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.

Assessment

CVSS: 9.4 (v4.0)
Severity: Critical
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 11 November 2026
Last updated: 11 November 2026
Affected: Checkmk GmbH · Checkmk
Assigner: Checkmk

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

At the source

EUVD (ENISA)

References

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