CVE-2025-39663

highpriority · track · 34EPSS 0.006 · 49 %ileDEEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.60% (49th) EPSS

CVSS 8.4 · high

Is it mine?

11 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

Cross-Site Scripting (XSS) vulnerability in Checkmk's distributed monitoring allows a compromised remote site to inject malicious HTML code into service outputs in the central site. Affecting Checkmk before 2.4.0p14, 2.3.0p39, 2.2.0 and 2.1.0 (eol).

cvss

Technical severity, 0–10. One row per scoring source.

8.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.9–8.5

v3.18.4highCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.7 · impact 6

v4.08.5highCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:Nsecondary · ENISA EU

v4.08.5highCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:H/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:Xsecondary · security@checkmk.com

v4.05.9mediumCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/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:Xsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimaryCWE-80US

affected products (11)

Products and version ranges known to be affected.

Checkmk Checkmk <2.3.0p39all versionscert_bundDE
Checkmk Checkmk <2.4.0p14all versionscert_bundDE
Checkmk Checkmk< 2.3.0p39cert_bundDE
Checkmk Checkmk< 2.4.0p14cert_bundDE
Checkmk GmbH Checkmk≤ 2.1.0enisa_euvdEU
Checkmk GmbH Checkmk≤ 2.2.0enisa_euvdEU
Checkmk GmbH Checkmk2.3.0 → 2.3.0p39enisa_euvdEU
Checkmk GmbH Checkmk2.4.0 → 2.4.0p14enisa_euvdEU
checkmk checkmk2.0.0 → 2.3.0nvdUScpe:2.3:a:checkmk:checkmk:*:*:*:*:*:*:*:*
checkmk checkmk= 2.3.0nvdUScpe:2.3:a:checkmk:checkmk:*:*:*:*:*:*:*:*
checkmk checkmk= 2.4.0nvdUScpe:2.3:a:checkmk:checkmk:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2025-2344Checkmk: Schwachstelle ermöglicht Cross-Site ScriptingDeutsch2025-10-20csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann eine Schwachstelle in Checkmk ausnutzen, um einen Cross-Site Scripting Angriff durchzuführen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd NVD CVE.org MITRE

published 2025-10-30modified 2026-10-19

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+53003 more

references (7)

External citations — patches, advisories, analysis.

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