CVE-2026-56177: Windows Server Elevation of Privilege Vulnerability
Published Sep 8, 2026
·Updated
Use after free in Windows Server allows an authorized attacker to elevate privileges locally.
Other sources
Windows Server Elevation of Privilege Vulnerability
— Microsoft
Affected Software
48 affected componentsFixes available
Microsoft Windows Server 2016<10.0.14393.9512
10.0.14393.9512
Microsoft Windows 10=1607
10.0.14393.9512
Microsoft Windows 10=21H2
10.0.19044.7725
Microsoft Windows Server 2025<10.0.26100.33438
10.0.26100.33438
Microsoft Windows 11=23H2
10.0.22631.7582
Microsoft Windows 10=1607
10.0.14393.9512
Microsoft Windows 11=26H1
10.0.28000.2954
Microsoft Windows 11=26H1
10.0.28000.2954
Microsoft Windows 11=24H2
10.0.26100.9445
Microsoft Windows 11=25H2
10.0.26200.9445
Microsoft Windows Server 2025<10.0.26100.33438
10.0.26100.33438
Microsoft Windows 11=25H2
10.0.26200.9445
Microsoft Windows 10=22H2
10.0.19045.7725
Microsoft Windows Server 2022<10.0.20348.5622
10.0.20348.5622
Microsoft Windows 10=22H2
10.0.19045.7725
Microsoft Windows 10=21H2
10.0.19044.7725
Microsoft Windows Server 2022<10.0.20348.5622
10.0.20348.5622
Microsoft Windows 10=22H2
10.0.19045.7725
Microsoft Windows Server 2016<10.0.14393.9512
10.0.14393.9512
Microsoft Windows Server 2019<10.0.17763.9245
10.0.17763.9245
Microsoft Windows 10=21H2
10.0.19044.7725
Microsoft Windows 10=1809
10.0.17763.9245
Microsoft Windows Server 2019<10.0.17763.9245
10.0.17763.9245
Microsoft Windows 11=24H2
10.0.26100.9445
Microsoft Windows 10=1809
10.0.17763.9245
Microsoft Windows 11=23H2
10.0.22631.7582
Microsoft Windows 10 1607<10.0.14393.9512
Microsoft Windows 10 1607<10.0.14393.9512
Microsoft Windows 10 1809<10.0.17763.9245
Microsoft Windows 10 1809<10.0.17763.9245
Microsoft Windows 10 21h2<10.0.19044.7725
Microsoft Windows 10 21h2<10.0.19044.7725
Microsoft Windows 10 21h2<10.0.19044.7725
Microsoft Windows 10 22h2<10.0.19045.7725
Microsoft Windows 10 22h2<10.0.19045.7725
Microsoft Windows 10 22h2<10.0.19045.7725
Microsoft Windows 11 23h2<10.0.22631.7582
Microsoft Windows 11 23h2<10.0.22631.7582
Microsoft Windows 11 24h2<10.0.26100.9445
Microsoft Windows 11 24h2<10.0.26100.9445
Microsoft Windows 11 25h2<10.0.26200.9445
Microsoft Windows 11 25h2<10.0.26200.9445
Microsoft Windows 11 26h1<10.0.28000.2954
Microsoft Windows 11 26h1<10.0.28000.2954
Microsoft Windows Server 2016<10.0.14393.9512
Microsoft Windows Server 2019<10.0.17763.9245
Microsoft Windows Server 2022<10.0.20348.5622
Microsoft Windows Server 2025<10.0.26100.33438
Remediation
Event History
Sep 8, 2026
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·02:00 PM
Affected Software
Updated
via Microsoft·02:00 PM
Description
CVE Published
via MITRE·05:14 PM
Data Sourced
via MITRE·05:14 PM
DescriptionSeverity
Data Sourced
via NVD·06:17 PM
RemedyDescriptionSeverityWeaknessAffected Software
Frequently Asked Questions
1
Who can exploit this vulnerability?
An attacker must already be authorized on an affected system and able to execute code locally. The vulnerability is not described as remotely exploitable or requiring user interaction.
2
Which systems are listed as affected?
The affected software list includes Microsoft Windows 10, Windows 11, Windows Server 2016, Windows Server 2019, Windows Server 2022, and Windows Server 2025.
3
What is the likely impact of successful exploitation?
Successful exploitation allows a local authorized attacker to elevate privileges. The provided severity vector indicates high potential impact to confidentiality, integrity, and availability.