Vulnerability-Lookup

GHSA-H7CW-JGMC-MWC6

Vulnerability from github – Published: 2026-06-08 15:32 – Updated: 2026-06-08 18:31

Details

Stored cross-site scripting in the service discovery active check output in Checkmk <2.5.0p5, <2.4.0p31, <2.3.0p48, and all 2.2.0 versions allows an administrator who can configure active or custom checks to inject malicious HTML or JavaScript into check output that executes in the browser of an admin or a user with host read permissions when they run the check on the service discovery page.

Severity

4.8 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

4.8 (Medium)


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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-9549"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-08T13:16:34Z",
    "severity": "MODERATE"
  },
  "details": "Stored cross-site scripting in the service discovery active check output in Checkmk \u003c2.5.0p5, \u003c2.4.0p31, \u003c2.3.0p48, and all 2.2.0 versions allows an administrator who can configure active or custom checks to inject malicious HTML or JavaScript into check output that executes in the browser of an admin or a user with host read permissions when they run the check on the service discovery page.",
  "id": "GHSA-h7cw-jgmc-mwc6",
  "modified": "2026-06-08T18:31:46Z",
  "published": "2026-06-08T15:32:59Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-9549"
    },
    {
      "type": "WEB",
      "url": "https://checkmk.com/werk/17993"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:L/VA:N/SC:N/SI:L/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",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-9549 (GCVE-0-2026-9549)

Vulnerability from cvelistv5 – Published: 2026-06-08 12:07 – Updated: 2026-06-08 13:02

Title

Fix XSS in service discovery active check output

Summary

Severity

4.8 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Assigner

Checkmk

References

1 reference

URL	Tags
https://checkmk.com/werk/17993	vendor-advisory

Impacted products

1 product

Vendor	Product	Version
Checkmk GmbH	Checkmk	Affected: 2.5.0 , < 2.5.0p5 (semver) Affected: 2.4.0 , < 2.4.0p31 (semver) Affected: 2.3.0 , < 2.3.0p48 (semver) Affected: 2.2.0 (semver)

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JSON

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        "metrics": [
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                "id": "CVE-2026-9549",
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                  },
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                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-08T13:02:10.372370Z",
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
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          "url": "https://checkmk.com/werk/17993"
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-H7CW-JGMC-MWC6

CVE-2026-9549 (GCVE-0-2026-9549)

Tags

Sightings

Nomenclature