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CVE-2026-85836 Microsoft CVE debrief

A Windows Kernel Elevation of Privilege Vulnerability exists due to a use-after-free weakness in the Windows Kernel. An authorized attacker could exploit this vulnerability locally to elevate privileges. This vulnerability affects Windows 11 versions 24H2, 25H2, 26H1, 26H2, and Windows Server 2025. Defenders should assess exposure and prioritize patching affected systems. The vulnerability has a high severity with a CVSS score of 7.8. The CVE record and NVD entry provide details on the vulnerability, but additional information on exploitation or impact is limited.

Vendor
Microsoft
Product
Windows 11 Version 24H2
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-10-13
Original CVE updated
2026-10-13
Advisory published
2026-10-13
Advisory updated
2026-10-13

Who should care

Defenders responsible for Windows systems, especially those with local access, should assess exposure and prioritize patching. This includes administrators of Windows 11 versions 24H2, 25H2, 26H1, 26H2, and Windows Server 2025. They should review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance. Security teams should plan vendor-supported updates or mitigations

Why it matters

CVE-2026-85836 is a high-severity vulnerability in the Windows Kernel that allows local privilege escalation. Defenders should prioritize patching affected systems and monitor for potential attacks.

  • Local privilege escalation is possible
  • Patching is required to prevent exploitation
  • Monitoring for local attacks is necessary

Technical summary

The Windows Kernel Elevation of Privilege Vulnerability (CVE-2026-85836) is caused by a use-after-free weakness in the Windows Kernel. This vulnerability allows an authorized attacker to elevate privileges locally. Affected products include Windows 11 versions 24H2, 25H2, 26H1, 26H2, and Windows Server 2025.

Defensive priority

Defenders should prioritize patching affected Windows systems, especially those exposed to local attacks.

Recommended defensive actions

  • Patch affected Windows systems immediately
  • Verify and apply updates for Windows 11 versions 24H2, 25H2, 26H1, 26H2, and Windows Server 2025
  • Monitor local system access and privilege escalation attempts

Evidence notes

The CVE record and NVD entry provide details on the vulnerability. However, additional information on exploitation or impact is limited. The vulnerability is caused by a use-after-free weakness in the Windows Kernel. Affected products include Windows 11 versions 24H2, 25H2, 26H1, 26H2, and Windows Server 2025. There is no information on public exploitation or specific attacks. Defenders should verify and apply updates for affected systems and monitor local system access and privilege

Sources and references

Verified primary and authoritative sources

  • CVE-2026-85836 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-85836

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-85836 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-85836

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Windows Kernel Elevation of Privilege Vulnerability

    Unverified legacy reference

    URL: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/85xxx/CVE-2026-85836.json

    cve_program_cvelist_v5

  • Source reference

    Unverified legacy reference

    URL: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85836

    Supplemental source - vendor-advisory, patch

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.