CVE-2026-71338

Double free in Windows Failover Cluster allows an authorized attacker to elevate privileges locally.

CVSS v3 6.4 MEDIUM

6.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 0.5 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-71338	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_10_1607:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_1607:::::::x86:*
	cpe:2.3:o:microsoft:windows_10_1809:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_1809:::::::x86:*
	cpe:2.3:o:microsoft:windows_server_2012:-:::::::*
	cpe:2.3:o:microsoft:windows_server_2012:r2:::::::*
	cpe:2.3:o:microsoft:windows_server_2016::::::::
	cpe:2.3:o:microsoft:windows_server_2019::::::::
	cpe:2.3:o:microsoft:windows_server_2022::::::::
	cpe:2.3:o:microsoft:windows_server_2025::::::::

History

No history.

Information

Published : 2026-09-08 18:20

Updated : 2026-09-15 13:07

NVD link : CVE-2026-71338

Mitre link : CVE-2026-71338

CVE.ORG link : CVE-2026-71338

JSON object : View

Products Affected

microsoft

windows_server_2019
windows_server_2012
windows_server_2016
windows_10_1607
windows_server_2022
windows_server_2025
windows_10_1809

CWE

CWE-415

Double Free

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"10.0.14393.0", "lessThan": "10.0.14393.9512", "versionType": "custom"}], "platforms": ["32-bit Systems", "x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows 10 Version 1809", "versions": [{"status": "affected", "version": "10.0.17763.0", "lessThan": "10.0.17763.9245", "versionType": "custom"}], "platforms": ["32-bit Systems", "x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2012", "versions": [{"status": "affected", "version": "6.2.9200.0", "lessThan": "6.2.9200.26349", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2012 (Server Core installation)", "versions": [{"status": "affected", "version": "6.2.9200.0", "lessThan": "6.2.9200.26349", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2012 R2", "versions": [{"status": "affected", "version": "6.3.9600.0", "lessThan": "6.3.9600.23397", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2012 R2 (Server Core installation)", "versions": [{"status": "affected", "version": "6.3.9600.0", "lessThan": "6.3.9600.23397", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2016", "versions": [{"status": "affected", "version": "10.0.14393.0", "lessThan": "10.0.14393.9512", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2016 (Server Core installation)", "versions": [{"status": "affected", "version": "10.0.14393.0", "lessThan": "10.0.14393.9512", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2019", "versions": [{"status": "affected", "version": "10.0.17763.0", "lessThan": "10.0.17763.9245", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2019 (Server Core installation)", "versions": [{"status": "affected", "version": "10.0.17763.0", "lessThan": "10.0.17763.9245", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2022", "versions": [{"status": "affected", "version": "10.0.20348.0", "lessThan": "10.0.20348.5622", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2025", "versions": [{"status": "affected", "version": "10.0.26100.0", "lessThan": "10.0.26100.33438", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2025 (Server Core installation)", "versions": [{"status": "affected", "version": "10.0.26100.0", "lessThan": "10.0.26100.33438", "versionType": "custom"}], "platforms": ["x64-based Systems"]}]}], "published": "2026-09-08T18:20:13.573", "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-71338", "tags": ["Patch", "Vendor Advisory"], "source": "secure@microsoft.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "secure@microsoft.com", "description": [{"lang": "en", "value": "CWE-415"}]}], "descriptions": [{"lang": "en", "value": "Double free in Windows Failover Cluster allows an authorized attacker to elevate privileges locally."}], "lastModified": "2026-09-15T13:07:56.120", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x64:*", "vulnerable": true, "matchCriteriaId": "F5BC051B-C14F-43DF-B3A2-A32EE0DDC142", "versionEndExcluding": "10.0.14393.9512"}, {"criteria": "cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:*", "vulnerable": true, "matchCriteriaId": "D8DA8FA6-35F6-4E0F-A9C0-37CB88186C5B", "versionEndExcluding": "10.0.14393.9512"}, {"criteria": 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