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CVE-2026-85837 Microsoft CVE debrief

A Windows Kernel Elevation of Privilege Vulnerability exists due to an out-of-bounds read in the Windows Kernel, allowing an authorized attacker to elevate privileges locally. This vulnerability affects multiple versions of Windows 11 and Windows Server 2025. Microsoft has released a patch for this vulnerability. The vulnerability is considered High severity with a CVSS score of 7.8. System administrators and security teams should assess exposure and apply patches. The CVE Program record and NVD vulnerability detail provide information on the vulnerability.

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

System administrators and security teams responsible for Windows systems, particularly those managing Windows 11 and Windows Server 2025 deployments, should assess exposure and apply patches to prevent local privilege escalation.

Why it matters

This vulnerability allows an authorized attacker to elevate privileges locally, potentially leading to system compromise. System administrators and security teams should assess exposure and apply patches.

  • Local privilege escalation is possible
  • Patching is required to prevent exploitation
  • System administrators should verify affected systems are updated

Technical summary

The Windows Kernel Elevation of Privilege Vulnerability exists due to an out-of-bounds read in the Windows Kernel. An authorized attacker can exploit this vulnerability to elevate privileges locally. The vulnerability affects Windows 11 Version 24H2, Windows 11 Version 25H2, Windows 11 version 26H1, Windows 11 Version 26H2, Windows Server 2025, and Windows Server 2025 (Server Core installation).

Defensive priority

High

Recommended defensive actions

  • Apply the Microsoft patch for CVE-2026-85837
  • Verify that affected systems are updated with the latest security patches
  • Monitor system logs for potential exploitation attempts

Evidence notes

The CVE Program record and NVD vulnerability detail provide information on the vulnerability. Microsoft has released a patch for this vulnerability. The vulnerability affects Windows 11 Version 24H2, Windows 11 Version 25H2, Windows 11 version 26H1, Windows 11 Version 26H2, Windows Server 2025, and Windows Server 2025 (Server Core installation).

Sources and references

Verified primary and authoritative sources

  • CVE-2026-85837 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-85837

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

  • CVE-2026-85837 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-85837

    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-2026-85837.json

    cve_program_cvelist_v5

  • Source reference

    Unverified legacy reference

    URL: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85837

    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.