{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-15937", "assignerOrgId": "f7d6281c-4801-44ce-ace2-493291dedb0f", "state": "PUBLISHED", "assignerShortName": "Checkmk", "dateReserved": "2026-07-16T08:40:57.255Z", "datePublished": "2026-09-04T08:24:49.802Z", "dateUpdated": "2026-09-04T08:24:49.802Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unaffected", "product": "Checkmk", "vendor": "Checkmk GmbH", "versions": [{"lessThan": "2.5.0p10", "status": "affected", "version": "2.5.0", "versionType": "semver"}]}], "credits": [{"lang": "en", "type": "reporter", "value": "PS Positive Security GmbH"}], "descriptions": [{"lang": "en", "value": "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."}], "impacts": [{"capecId": "CAPEC-114", "descriptions": [{"lang": "en", "value": "CAPEC-114: Authentication Abuse"}]}], "metrics": [{"cvssV4_0": {"baseScore": 5.3, "baseSeverity": "MEDIUM", "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", "version": "4.0"}}], "problemTypes": [{"descriptions": [{"cweId": "CWE-295", "description": "CWE-295: Improper Certificate Validation", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "f7d6281c-4801-44ce-ace2-493291dedb0f", "shortName": "Checkmk", "dateUpdated": "2026-09-04T08:24:49.802Z"}, "references": [{"tags": ["vendor-advisory"], "url": "https://checkmk.com/werk/19735"}], "title": "Agent receiver certificate confusion allows authentication with a certificate issued for another endpoint", "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:checkmk:checkmk:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.5.0", "versionEndExcluding": "2.5.0p10"}]}]}]}}}

{}

{"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 <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."}], "id": "CVE-2026-15937", "lastModified": "2026-09-04T09:17:10.410", "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"}]}, "published": "2026-09-04T09:17:10.410", "references": [{"source": "security@checkmk.com", "url": "https://checkmk.com/werk/19735"}], "sourceIdentifier": "security@checkmk.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-295"}], "source": "security@checkmk.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[2.5.0,2.5.0p10)"}}], "enrichment": {"confidence": 95.0, "confidence_source": "inferred", "scores": [{"score": 95.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Checkmk", "source": "cna", "vendor": "Checkmk GmbH"}, "product": "checkmk", "vendor": "checkmk"}], "created": "2026-09-04T09:30:04.035484+00:00", "updated": "2026-09-04T12:30:17.144769+00:00", "vendors": ["checkmk", "checkmk$PRODUCT$checkmk"]}