CVE-2026-83756: Windows Win32 Kernel Subsystem Elevation of Privilege Vulnerability

Published Oct 13, 2026
·
Updated

Use after free in Windows Win32 Kernel Subsystem allows an authorized attacker to elevate privileges locally.

Other sources

Windows Win32 Kernel Subsystem Elevation of Privilege Vulnerability

— Microsoft

Affected Software

21 affected componentsFixes available
Microsoft Win32 Kernel Subsystem
Microsoft Windows 11=23H2
10.0.22631.7652
Microsoft Windows Server 2022<10.0.20348.5761
10.0.20348.5761
Microsoft Windows 11=26H2
10.0.26300.9711
Microsoft Windows 10=21H2
10.0.19044.7807
Microsoft Windows 11=26H1
10.0.28000.3231
Microsoft Windows 11=23H2
10.0.22631.7652
Microsoft Windows 11=24H2
10.0.26100.9711
Microsoft Windows 10=21H2
10.0.19044.7807
Microsoft Windows 11=26H2
10.0.26300.9711
Microsoft Windows Server 2025<10.0.26100.33650
10.0.26100.33650
Microsoft Windows 11=25H2
10.0.26200.9711
Microsoft Windows 11=26H1
10.0.28000.3231
Microsoft Windows 10=22H2
10.0.19044.7807
Microsoft Windows 10=21H2
10.0.19044.7807
Microsoft Windows 11=25H2
10.0.26200.9711
Microsoft Windows Server 2022<10.0.20348.5761
10.0.20348.5761
Microsoft Windows 10=22H2
10.0.19044.7807
Microsoft Windows 11=24H2
10.0.26100.9711
Microsoft Windows 10=22H2
10.0.19044.7807
Microsoft Windows Server 2025<10.0.26100.33650
10.0.26100.33650

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.22631.7652Patch KB5126653
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.26300.9711Patch KB5127648
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.19044.7807Patch KB5126657
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.20348.5761Patch KB5126655
  5. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.28000.3231Patch KB5127646
  6. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.26100.9711Patch KB5127648
  7. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.26100.33650Patch KB5126646
  8. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.26200.9711Patch KB5127648

Event History

Oct 13, 2026
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeaknessAffected Software
CVE Published
via MITRE·07:00 PM
Data Sourced
via MITRE·07:00 PM
DescriptionSeverity

Frequently Asked Questions

1

What level of access does an attacker need to exploit this issue?

An attacker must already be authorized to access the affected Windows system and exploit the flaw locally. The vulnerability does not indicate remote exploitation or a user-interaction requirement.

2

Which systems should be evaluated for exposure?

Evaluate Microsoft Windows 10, Windows 11, Windows Server 2022, and Windows Server 2025 systems that include the Microsoft Win32 Kernel Subsystem. The provided information does not identify unaffected versions, configurations, or mitigations.

3

What is the likely impact after successful exploitation?

Successful exploitation can allow local elevation of privilege and has high confidentiality, integrity, and availability impact. An attacker could gain privileges beyond those of their existing authorized account.

Contact

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