CVE-2026-100201: Windows Client License Service Elevation of Privilege Vulnerability

Published Oct 13, 2026
·
Updated

Heap-based buffer overflow in Windows Client License Service allows an authorized attacker to elevate privileges locally.

Other sources

Windows Client License Service Elevation of Privilege Vulnerability

— Microsoft

Affected Software

25 affected componentsFixes available
Microsoft Windows Server 2019<10.0.17763.9376
10.0.17763.9376
Microsoft Windows 11=26H1
10.0.28000.3231
Microsoft Windows 11=24H2
10.0.26100.9711
Microsoft Windows Server 2025<10.0.26100.33650
10.0.26100.33650
Microsoft Windows Server 2025<10.0.26100.33650
10.0.26100.33650
Microsoft Windows 10=21H2
10.0.19044.7807
Microsoft Windows 11=25H2
10.0.26200.9711
Microsoft Windows 11=26H1
10.0.28000.3231
Microsoft Windows 11=24H2
10.0.26100.9711
Microsoft Windows 11=26H2
10.0.26300.9711
Microsoft Windows 11=26H2
10.0.26300.9711
Microsoft Windows 11=23H2
10.0.22631.7652
Microsoft Windows 11=23H2
10.0.22631.7652
Microsoft Windows Server 2022<10.0.20348.5761
10.0.20348.5761
Microsoft Windows 10=22H2
10.0.19044.7807
Microsoft Windows 10=22H2
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=21H2
10.0.19044.7807
Microsoft Windows 10=22H2
10.0.19044.7807
Microsoft Windows Server 2019<10.0.17763.9376
10.0.17763.9376
Microsoft Windows 10=21H2
10.0.19044.7807
Microsoft Windows 10=1809
10.0.17763.9376
Microsoft Windows 10=1809
10.0.17763.9376
Microsoft Windows Client License Service

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 10.0.28000.3231Patch KB5127646
  2. Upgrade

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

    Fixed in 10.0.17763.9376Patch KB5126651
  3. Upgrade

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

    Fixed in 10.0.26100.9711Patch KB5127648
  4. Upgrade

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

    Fixed in 10.0.26100.33650Patch KB5126646
  5. Upgrade

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

    Fixed in 10.0.26200.9711Patch KB5127648
  6. Upgrade

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

    Fixed in 10.0.19044.7807Patch KB5126657
  7. Upgrade

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

    Fixed in 10.0.26300.9711Patch KB5127648
  8. Upgrade

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

    Fixed in 10.0.22631.7652Patch KB5126653
  9. Upgrade

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

    Fixed in 10.0.20348.5761Patch KB5126655

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·07:01 PM
Data Sourced
via MITRE·07:01 PM
DescriptionSeverity
Data Sourced
via NVD·07:17 PM
DescriptionSeverityWeakness

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