CVE-2026-120495

Arbitrary file write and code execution via crafted Synthetic Monitoring agent data

Published Nov 11, 2026 CVSS 4.0 · 9.4 Critical EPSS < 1% KEV · Not listed
Description
Path traversal in the Synthetic Monitoring "Robotmk" test service of Checkmk <2.5.0p19, <2.4.0p40, and 2.3.0 (EOL) allows an attacker who controls the agent output of a monitored host's check output for a host to inject a crafted robot output to define the contents and location for the generated HTML log, leading to code execution as the site user.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
References
History
Type Values Removed Values Added
Description Path traversal in the Synthetic Monitoring "Robotmk" test service of Checkmk <2.5.0p19, <2.4.0p40, and 2.3.0 (EOL) allows an attacker who controls the agent output of a monitored host's check output for a host to inject a crafted robot output to define the contents and location for the generated HTML log, leading to code execution as the site user.
Title Arbitrary file write and code execution via crafted Synthetic Monitoring agent data
First Time appeared Checkmk
Checkmk checkmk
Weaknesses CWE-23
CPEs cpe:2.3:a:checkmk:checkmk:*:*:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.3.0:*:*:*:*:*:*:*
Vendors & Products Checkmk
Checkmk checkmk
References
Metrics cvssV4_0

{'score': 9.4, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Checkmk
Published
Updated
Nov 11, 2026, 10:46 AM
Reserved
Nov 2, 2026, 2:44 PM
Status
Deferred
Published
Nov 11, 2026, 11:17 AM
Modified
Nov 11, 2026, 11:17 AM