Read the docs
TI-2026-27556 Aliases CVE-2026-35420GHSA-g3c9-x495-5rjg

Windows Kernel Elevation of Privilege Vulnerability

Priority LOW 36CWE-122Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Privilege escalation
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Microsoft. Impact type from Microsoft.

Summary

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

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0032 25th percentileScored 2026-11-07
Fix Fixed Microsoft: 9 updates

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftWindows Server 20126.2.9200.0 to before 6.2.9200.260796.2.9200.26079Patch availableCNA
MicrosoftWindows Server 2012 (Server Core installation)6.2.9200.0 to before 6.2.9200.260796.2.9200.26079Patch availableCNA
MicrosoftWindows Server 2012 R26.3.9600.0 to before 6.3.9600.231816.3.9600.23181Patch availableCNA
MicrosoftWindows Server 2012 R2 (Server Core installation)6.3.9600.0 to before 6.3.9600.231816.3.9600.23181Patch availableCNA
MicrosoftWindows Server 201610.0.14393.0 to before 10.0.14393.914010.0.14393.9140Patch availableCNA
MicrosoftWindows Server 2016 (Server Core installation)10.0.14393.0 to before 10.0.14393.914010.0.14393.9140Patch availableCNA
MicrosoftWindows Server 201910.0.17763.0 to before 10.0.17763.875510.0.17763.8755Patch availableCNA
MicrosoftWindows Server 2019 (Server Core installation)10.0.17763.0 to before 10.0.17763.875510.0.17763.8755Patch availableCNA
MicrosoftWindows Server 202210.0.20348.0 to before 10.0.20348.513910.0.20348.5139Patch availableCNA
MicrosoftWindows Server 2022, 23H2 Edition (Server Core installation)10.0.25398.0 to before 10.0.25398.233010.0.25398.2330Patch availableCNA
MicrosoftWindows Server 202510.0.26100.0 to before 10.0.26100.3286010.0.26100.32860Patch availableCNA
MicrosoftWindows Server 2025 (Server Core installation)10.0.26100.0 to before 10.0.26100.3286010.0.26100.32860Patch availableCNA
  • Windows Server 2012 VendorMicrosoft Affected 6.2.9200.0 to before 6.2.9200.26079 Fixed in 6.2.9200.26079 Patch available CNA
  • Windows Server 2012 (Server Core installation) VendorMicrosoft Affected 6.2.9200.0 to before 6.2.9200.26079 Fixed in 6.2.9200.26079 Patch available CNA
  • Windows Server 2012 R2 VendorMicrosoft Affected 6.3.9600.0 to before 6.3.9600.23181 Fixed in 6.3.9600.23181 Patch available CNA
  • Windows Server 2012 R2 (Server Core installation) VendorMicrosoft Affected 6.3.9600.0 to before 6.3.9600.23181 Fixed in 6.3.9600.23181 Patch available CNA
  • Windows Server 2016 VendorMicrosoft Affected 10.0.14393.0 to before 10.0.14393.9140 Fixed in 10.0.14393.9140 Patch available CNA
  • Windows Server 2016 (Server Core installation) VendorMicrosoft Affected 10.0.14393.0 to before 10.0.14393.9140 Fixed in 10.0.14393.9140 Patch available CNA
  • Windows Server 2019 VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.8755 Fixed in 10.0.17763.8755 Patch available CNA
  • Windows Server 2019 (Server Core installation) VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.8755 Fixed in 10.0.17763.8755 Patch available CNA
  • Windows Server 2022 VendorMicrosoft Affected 10.0.20348.0 to before 10.0.20348.5139 Fixed in 10.0.20348.5139 Patch available CNA
  • Windows Server 2022, 23H2 Edition (Server Core installation) VendorMicrosoft Affected 10.0.25398.0 to before 10.0.25398.2330 Fixed in 10.0.25398.2330 Patch available CNA
  • Windows Server 2025 VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.32860 Fixed in 10.0.26100.32860 Patch available CNA
  • Windows Server 2025 (Server Core installation) VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.32860 Fixed in 10.0.26100.32860 Patch available CNA

CPE configurations NVD · 7

CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*not specified by NVDVulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*r2VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*before 10.0.14393.9140VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*before 10.0.17763.8755VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*before 10.0.20348.5074VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:*before 10.0.25398.2330VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*before 10.0.26100.32772VulnerableMicrosoft
  • cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:* Versions r2 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:* Versions before 10.0.14393.9140 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:* Versions before 10.0.17763.8755 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:* Versions before 10.0.20348.5074 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:* Versions before 10.0.25398.2330 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:* Versions before 10.0.26100.32772 Vulnerable ·Microsoft

Remediation

Microsoft 9 updates

  • KB5087545
    Security Update
    • Windows Server 2022 10.0.20348.5139
    • Windows Server 2022 (Server Core installation) 10.0.20348.5139
  • KB5087541
    Security Update
    • Windows Server 2022, 23H2 Edition (Server Core installation) 10.0.25398.2330
  • KB5087539
    Security Update
    • Windows Server 2025 10.0.26100.32860
    • Windows Server 2025 (Server Core installation) 10.0.26100.32860
Show 6 more Microsoft updates
  • KB5087538
    Security Update
    • Windows 10 Version 1809 for 32-bit Systems 10.0.17763.8755
    • Windows 10 Version 1809 for x64-based Systems 10.0.17763.8755
    • Windows Server 2019 10.0.17763.8755
    • Windows Server 2019 (Server Core installation) 10.0.17763.8755
  • KB5087537
    Security Update
    • Windows 10 Version 1607 for 32-bit Systems 10.0.14393.9140
    • Windows 10 Version 1607 for x64-based Systems 10.0.14393.9140
    • Windows Server 2016 10.0.14393.9140
    • Windows Server 2016 (Server Core installation) 10.0.14393.9140
  • KB5087471
    Monthly Rollup
    • Windows Server 2012 R2 6.3.9600.23181
    • Windows Server 2012 R2 (Server Core installation) 6.3.9600.23181
  • KB5087470
    Monthly Rollup
    • Windows Server 2012 6.2.9200.26079
    • Windows Server 2012 (Server Core installation) 6.2.9200.26079
  • KB5087424
    Security Hotpatch Update
    • Windows Server 2022 10.0.20348.5074
    • Windows Server 2022 (Server Core installation) 10.0.20348.5074
  • KB5087423
    Security Hotpatch Update
    • Windows Server 2025 10.0.26100.32772
    • Windows Server 2025 (Server Core installation) 10.0.26100.32772

Vendor assessments

Microsoft

Microsoft's page for this CVE →

Impact
Elevation of Privilege
Exploited
No
Publicly disclosed
No
Exploitability
Exploitation Less Likely

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-35420
  2. 2026-10-03 Alias added: GHSA-g3c9-x495-5rjg

References

Patch 1

  • TI-2025-36863 Windows Server Update Service (WSUS) Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2020-01431 Netlogon Elevation of Privilege Vulnerability KEVCVSS 3.1CRITICAL 10.0
  • TI-2020-01310 Improper input validation in Microsoft Windows Server KEVCVSS 3.1CRITICAL 10.0
  • TI-2017-06077 Microsoft Windows XP SP3, Windows XP x64 XP2, Windows Server 2003 SP2, Windows Vista… KEVCVSS 3.1CRITICAL 9.8
  • TI-2015-01465 HTTP.sys in Microsoft Windows 7 SP1, Windows Server 2008 R2 SP1, Windows 8, Windows 8.1… KEVCVSS 3.1CRITICAL 9.8
  • TI-2020-01009 Improper input validation in Microsoft Windows Server KEVCVSS 3.1CRITICAL 9.0
See all 5293 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences