CVE-2026-66307

{"id": "CVE-2026-66307", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-66307", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-09-08T19:14:13.483335Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "secure@microsoft.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 3.9}]}, "affected": [{"source": "secure@microsoft.com", "affectedData": [{"vendor": "Microsoft", "product": "Skype for Business Server 2015 CU13", "versions": [{"status": "affected", "version": "9319.0", "lessThan": "6.0.9319.885", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Skype for Business Server 2019 CU8", "versions": [{"status": "affected", "version": "2046.0", "lessThan": "7.0.2046.569", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Skype for Business Server Subscription Edition CU1", "versions": [{"status": "affected", "version": "2046.0", "lessThan": "7.0.2046.879", "versionType": "custom"}], "platforms": ["x64-based Systems"]}]}], "published": "2026-09-08T19:18:08.327", "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66307", "source": "secure@microsoft.com"}], "vulnStatus": "Undergoing Analysis", "weaknesses": [{"type": "Secondary", "source": "secure@microsoft.com", "description": [{"lang": "en", "value": "CWE-191"}]}], "descriptions": [{"lang": "en", "value": "Integer underflow (wrap or wraparound) in Skype for Business allows an unauthorized attacker to deny service over a network."}], "lastModified": "2026-09-08T20:17:38.257", "sourceIdentifier": "secure@microsoft.com"}