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"10.0.19045.0", "versionType": "custom"}]}, {"platforms": ["ARM64-based Systems"], "product": "Windows 11 version 23H2", "vendor": "Microsoft", "versions": [{"lessThan": "10.0.22631.7582", "status": "affected", "version": "10.0.22631.0", "versionType": "custom"}]}, {"platforms": ["x64-based Systems"], "product": "Windows 11 Version 23H2", "vendor": "Microsoft", "versions": [{"lessThan": "10.0.22631.7582", "status": "affected", "version": "10.0.22631.0", "versionType": "custom"}]}, {"platforms": ["ARM64-based Systems", "x64-based Systems"], "product": "Windows 11 Version 24H2", "vendor": "Microsoft", "versions": [{"lessThan": "10.0.26100.9445", "status": "affected", "version": "10.0.26100.0", "versionType": "custom"}]}, {"platforms": ["ARM64-based Systems", "x64-based Systems"], "product": "Windows 11 Version 25H2", "vendor": "Microsoft", "versions": [{"lessThan": "10.0.26200.9445", "status": "affected", "version": "10.0.26200.0", "versionType": "custom"}]}, {"platforms": ["ARM64-based Systems", "x64-based Systems"], "product": "Windows 11 version 26H1", "vendor": "Microsoft", "versions": [{"lessThan": "10.0.28000.2954", "status": "affected", "version": "10.0.28000.0", "versionType": "custom"}]}, {"platforms": ["x64-based Systems"], "product": "Windows Server 2012", "vendor": "Microsoft", "versions": [{"lessThan": "6.2.9200.26349", "status": "affected", "version": "6.2.9200.0", "versionType": "custom"}]}, {"platforms": ["x64-based Systems"], "product": "Windows Server 2012 (Server Core installation)", "vendor": "Microsoft", "versions": [{"lessThan": "6.2.9200.26349", "status": "affected", "version": "6.2.9200.0", "versionType": "custom"}]}, {"platforms": ["x64-based Systems"], "product": "Windows Server 2012 R2", "vendor": "Microsoft", "versions": [{"lessThan": "6.3.9600.23397", "status": "affected", "version": "6.3.9600.0", "versionType": "custom"}]}, {"platforms": ["x64-based Systems"], "product": "Windows Server 2012 R2 (Server Core installation)", "vendor": "Microsoft", "versions": [{"lessThan": "6.3.9600.23397", "status": "affected", "version": "6.3.9600.0", "versionType": "custom"}]}, {"platforms": ["x64-based Systems"], "product": "Windows Server 2016", "vendor": "Microsoft", "versions": [{"lessThan": "10.0.14393.9512", "status": "affected", "version": "10.0.14393.0", "versionType": "custom"}]}, {"platforms": ["x64-based Systems"], "product": "Windows Server 2016 (Server Core installation)", "vendor": "Microsoft", "versions": [{"lessThan": "10.0.14393.9512", "status": "affected", "version": "10.0.14393.0", "versionType": "custom"}]}, {"platforms": ["x64-based Systems"], "product": "Windows Server 2019", "vendor": "Microsoft", "versions": [{"lessThan": "10.0.17763.9245", "status": "affected", "version": "10.0.17763.0", "versionType": "custom"}]}, {"platforms": ["x64-based Systems"], "product": "Windows Server 2019 (Server Core installation)", "vendor": "Microsoft", "versions": [{"lessThan": "10.0.17763.9245", "status": "affected", "version": "10.0.17763.0", "versionType": "custom"}]}, {"platforms": ["x64-based Systems"], "product": "Windows Server 2022", "vendor": "Microsoft", "versions": [{"lessThan": "10.0.20348.5622", "status": "affected", "version": "10.0.20348.0", "versionType": "custom"}]}, {"platforms": ["x64-based Systems"], "product": "Windows Server 2025", "vendor": "Microsoft", "versions": [{"lessThan": "10.0.26100.33438", "status": "affected", "version": "10.0.26100.0", "versionType": "custom"}]}, {"platforms": ["x64-based Systems"], "product": "Windows Server 2025 (Server Core installation)", "vendor": "Microsoft", "versions": [{"lessThan": "10.0.26100.33438", "status": "affected", "version": "10.0.26100.0", "versionType": "custom"}]}], "source": "secure@microsoft.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Installer allows an authorized attacker to elevate privileges locally."}], "id": "CVE-2026-77894", "lastModified": "2026-09-08T20:18:26.973", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.0, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.0, "impactScore": 5.9, "source": "secure@microsoft.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-77894", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-09-08T18:57:13.754927Z", "version": "2.0.3"}}]}, "published": "2026-09-08T18:20:39.367", "references": [{"source": "secure@microsoft.com", "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-77894"}], "sourceIdentifier": "secure@microsoft.com", "vulnStatus": "Undergoing Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-362"}, {"lang": "en", "value": "CWE-416"}], "source": "secure@microsoft.com", "type": "Secondary"}]}

{}

{}