PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-62766 Microsoft CVE debrief

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-08-11T17:04:21.233Z and has not been modified since then. The NVD entry is currently unclassified. This elevation of privilege vulnerability in Windows Kerberos, detailed in CVE-2026-62766, affects Windows 11 Version 24H2, 25H2, 26H1, and Windows Server 2025. Defenders should assess exposure and prioritize patching, especially for systems with local access. The vulnerability allows an authorized attacker to elevate privileges locally due to a double free in Windows Kerberos.

Vendor
Microsoft
Product
Windows 11 Version 24H2
CVSS
HIGH 7
CISA KEV
Not listed in stored evidence
Original CVE published
2026-08-11
Original CVE updated
2026-10-08
Advisory published
2026-08-11
Advisory updated
2026-10-08

Who should care

Defenders responsible for Windows 11 and Windows Server 2025 systems, especially those with local access, should assess exposure and prioritize patching.

Why it matters

CVE-2026-62766 is a high-severity elevation of privilege vulnerability in Windows Kerberos. Defenders should prioritize verifying exposure and applying patches.

  • Verify exposure of Windows 11 and Windows Server 2025 systems
  • Assess local access controls and Kerberos configuration
  • Prioritize patching for systems with local access

Technical summary

A double free vulnerability in Windows Kerberos allows an authorized attacker to elevate privileges locally. Affected products include Windows 11 Version 24H2, 25H2, 26H1, and Windows Server 2025. Defenders should prioritize verifying exposure of these systems to this elevation of privilege vulnerability, especially those with local access. Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.

Defensive priority

Defenders should prioritize verifying exposure of Windows 11 and Windows Server 2025 systems to this elevation of privilege vulnerability, especially those with local access.

Recommended defensive actions

  • Verify exposure of Windows 11 Version 24H2, 25H2, 26H1 and Windows Server 2025 systems to this elevation of privilege vulnerability
  • Assess local access controls and Kerberos configuration
  • Apply patches from Microsoft as available

Evidence notes

The CVE record and source item provide details on the vulnerability, but limited information is available on exploitation or impact. There is no evidence of public exploitation, but defenders should verify exposure of affected systems, including Windows 11 Version 24H2, 25H2, 26H1, and Windows Server 2025. Review official advisories and CVE records for further details. Assess local access controls and Kerberos configuration to prioritize patching.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-62766 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-62766

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

  • CVE-2026-62766 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-62766

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

Supplemental references

  • Windows Kerberos Elevation of Privilege Vulnerability

    Unverified legacy reference

    URL: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/62xxx/CVE-2026-62766.json

    cve_program_cvelist_v5

  • Source reference

    Unverified legacy reference

    URL: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62766

    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.