CVE-2026-33456

Potential livestatus injection in notification test

5.1 Medium

Livestatus injection in the notification test mode in Checkmk <2.5.0b4 and <2.4.0p26 allows an authenticated user with access to the notification test page to inject arbitrary Livestatus commands via a crafted service description.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: High
User interaction: None

What an attacker can affect

Confidentiality: Low
Integrity: Low
Availability: Low

Exploit likelihood

0.20%Up 0.2 points since Apr 10, 2026

What each source reports

CVE List Score used 5.1

Potential livestatus injection in notification test

Record: CVE-2026-33456
CVSS 4.0: 5.1 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
Weakness: CWE-140
Updated: 2026-11-02

EUVDEUVD-2026-21344 5.1

Record: EUVD-2026-21344
CVSS 4.0: 5.1 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
Updated: 2026-11-02

GitHub AdvisoriesGHSA-hxwv-vc7p-p66g 5.1

Livestatus injection in the notification test mode in Checkmk <2.5.0b4 and <2.4.0p26 allows an...

Record: GHSA-hxwv-vc7p-p66g
CVSS 4.0: 5.1 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/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
CVSS 3.1: 7.6 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
Weakness: CWE-140
Updated: 2026-11-02

NVD 5.1

Record: CVE-2026-33456
CVSS 4.0: 5.1 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/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
CVSS 3.1: 7.6 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
Weakness: CWE-140
Updated: 2026-11-02

OSV 5.1

Potential livestatus injection in notification test

Record: CVE-2026-33456
CVSS 4.0: 5.1 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
Weakness: CWE-140
Updated: 2026-11-02

OSVUBUNTU-CVE-2026-33456 5.1

Record: UBUNTU-CVE-2026-33456
CVSS 4.0: 5.1 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
CVSS 3.1: 7.6 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
Updated: 2026-11-02

Affected products

Affected packages

Affected packages
Package	Affected	Fixed
`check-mk` Ubuntu:Pro:16.04:LTS	All versions, plus listed versions 1.2.6p5-11.2.6p12-11.2.6p12-1ubuntu0.16.04.11.2.6p12-1ubuntu0.16.04.1+esm1	None known
`check-mk` Ubuntu:18.04:LTS	All versions, plus listed versions 1.2.8p16-1ubuntu0.11.2.8p16-1ubuntu0.2	None known

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-33456 is a medium vulnerability (CVSS 5.1) in Checkmk, published April 10, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.20%, the 9th percentile. No source names a fixed version.