CVE-2026-83866 Windows Win32k Elevation of Privilege Vulnerability

{
  "id": "7e6b530e8937d8d0964ea6e2ca591ed1776f8f95bcfe96d1f6efbc7d5fb2ea93",
  "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83866",
  "method": "llm",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2026-83866 Windows Win32k Elevation of Privilege Vulnerability",
    "summary": "A use-after-free vulnerability in Windows Win32K could allow an authorized attacker to elevate privileges locally.",
    "evidence": "Use after free in Windows Win32K allows an authorized attacker to elevate privileges locally.",
    "products": [
      {
        "name": {
          "value": "Windows Win32K",
          "evidence": "Use after free in Windows Win32K"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "fixed_cves": [],
    "related_cves": [
      {
        "value": "CVE-2026-83866",
        "evidence": "CVE-2026-83866 Windows Win32k Elevation of Privilege Vulnerability"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "official-microsoft-security-updates",
  "document_id": 25020,
  "published_at": "2026-10-13T14:00:00+00:00"
}