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CVE-2026-62788 Microsoft CVE debrief

A use-after-free vulnerability in the Windows Kernel allows 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 a high-severity issue that requires immediate attention from system administrators and security teams. Affected systems include Windows 11 version 23H2, Windows 11 Version 24H2, Windows 11 Version 25H2, Windows 11 version 26H1, Windows Server 2025, and Windows Server 2025 (Server Core installation). The CVE Program and NVD provide official records of this vulnerability, and Microsoft has released a vendor with

Vendor
Microsoft
Product
Windows 11 version 23H2
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

System administrators and security teams responsible for Windows 11 and Windows Server 2025 systems should assess exposure and apply patches immediately to prevent local privilege escalation attacks.

Why it matters

CVE-2026-62788 is a high-severity vulnerability in the Windows Kernel that allows local privilege escalation. System administrators and security teams should assess exposure and apply patches immediately to prevent exploitation.

  • Local privilege escalation, allowing attackers to gain elevated access
  • Potential for lateral movement within compromised systems
  • Need for immediate patching to prevent exploitation
  • Verification of system configurations and inventory checks for affected versions

Technical summary

The vulnerability is a use-after-free issue in the Windows Kernel, allowing an authorized attacker to elevate privileges locally. Affected systems include Windows 11 version 23H2, Windows 11 Version 24H2, Windows 11 Version 25H2, Windows 11 version 26H1, Windows Server 2025, and Windows Server 2025 (Server Core installation).

Defensive priority

Apply patches immediately for Windows 11 and Windows Server 2025 systems, especially those exposed to local attacks.

Recommended defensive actions

  • Apply patches for Windows 11 version 23H2, Windows 11 Version 24H2, Windows 11 Version 25H2, Windows 11 version 26H1, Windows Server 2025, and Windows Server 2025 (Server Core installation)
  • Verify and apply patches for affected systems
  • Monitor systems for potential exploitation attempts

Evidence notes

The CVE Program and NVD provide official records of this vulnerability. Microsoft has released a vendor advisory with patches for affected systems. The vulnerability affects multiple versions of Windows 11 and Windows Server 2025, including Windows 11 version 23H2, Windows 11 Version 24H2, Windows 11 Version 25H2, Windows 11 version 26H1, Windows Server 2025, and Windows Server 2025 (Server Core installation). Defenders should verify system configurations and inventory checks for

Sources and references

Verified primary and authoritative sources

  • CVE-2026-62788 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-62788

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

  • CVE-2026-62788 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-62788

    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/2026/62xxx/CVE-2026-62788.json

    cve_program_cvelist_v5

  • Source reference

    Unverified legacy reference

    URL: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62788

    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.