CVE-2026-120495
Arbitrary file write and code execution via crafted Synthetic Monitoring agent data
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
What each source reports
CVE List Score used
9.4
Arbitrary file write and code execution via crafted Synthetic Monitoring agent data
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.
- Record
CVE-2026-120495- CVSS 4.0
- 9.4 Critical
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 - Weakness
- CWE-23
- Updated
- 2026-11-11
EUVDEUVD-2026-123351
9.4
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.
- Record
EUVD-2026-123351- CVSS 4.0
- 9.4 Critical
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 - Updated
- 2026-11-11
GitHub AdvisoriesGHSA-79m2-wqr8-q2wm
9.4
Path traversal in the Synthetic Monitoring "Robotmk" test service of Checkmk <2.5.0p19, <2.4.0p40...
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.
- Record
GHSA-79m2-wqr8-q2wm- CVSS 4.0
- 9.4 Critical
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-23
- Updated
- 2026-11-11
NVD
9.4
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.
- Record
CVE-2026-120495- CVSS 4.0
- 9.4 Critical
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-23
- Updated
- 2026-11-11
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| published | EUVD, NVD | |
| published | EUVD | |
| aliases, references | GitHub Advisories | |
| aliases, published | EUVD | |
| first indexed | CVE List |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-120495 is a critical vulnerability (CVSS 9.4) in Checkmk Gmbh Checkmk, published November 11, 2026. No source lists public exploit code. No source names a fixed version.