FKIE_CVE-2026-15937

Vulnerability from fkie_nvd - Published: 2026-09-04 09:17 - Updated: 2026-09-08 14:10
Severity
5.3 (Medium) - CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
Summary
Improper certificate validation in Checkmk <2.5.0p10 allows a relay and a push agent that share the same UUID to reuse each other's mTLS certificate to authenticate against agent receiver endpoints in either direction, because the endpoints do not verify that the certificate was issued by their own root certificate.
References
security@checkmk.comhttps://checkmk.com/werk/19735
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Checkmk",
          "vendor": "Checkmk GmbH",
          "versions": [
            {
              "lessThan": "2.5.0p10",
              "status": "affected",
              "version": "2.5.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "security@checkmk.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Improper certificate validation in Checkmk \u003c2.5.0p10 allows a relay and a push agent that share the same UUID to reuse each other\u0027s mTLS certificate to authenticate against agent receiver endpoints in either direction, because the endpoints do not verify that the certificate was issued by their own root certificate."
    }
  ],
  "id": "CVE-2026-15937",
  "lastModified": "2026-09-08T14:10:24.113",
  "metrics": {
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "LOW",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/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",
          "version": "4.0",
          "vulnAvailabilityImpact": "NONE",
          "vulnConfidentialityImpact": "LOW",
          "vulnIntegrityImpact": "LOW",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "security@checkmk.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-15937",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-04T19:39:13.186762Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-04T09:17:10.410",
  "references": [
    {
      "source": "security@checkmk.com",
      "url": "https://checkmk.com/werk/19735"
    }
  ],
  "sourceIdentifier": "security@checkmk.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-295"
        }
      ],
      "source": "security@checkmk.com",
      "type": "Secondary"
    }
  ]
}



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