CVE-2026-83645 Active Directory Federation Services (AD FS) Denial of Service Vulnerability

{
  "id": "4a5cec385e7f479bdc51b1857109b6ee8a558d426c734a7e73b993e25cfcadea",
  "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83645",
  "method": "llm",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2026-83645 Active Directory Federation Services (AD FS) Denial of Service Vulnerability",
    "summary": "An unauthorized attacker could deny service over a network by causing unbounded resource allocation in AD FS.",
    "evidence": "Allocation of resources without limits or throttling in Active Directory Federation Services (AD FS) allows an unauthorized attacker to deny service over a network.",
    "products": [
      {
        "name": {
          "value": "Active Directory Federation Services (AD FS)",
          "evidence": "Allocation of resources without limits or throttling in Active Directory Federation Services (AD FS) allows an unauthorized attacker to deny service over a network."
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "fixed_cves": [],
    "related_cves": [
      {
        "value": "CVE-2026-83645",
        "evidence": "CVE-2026-83645 Active Directory Federation Services (AD FS) Denial of Service Vulnerability"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "official-microsoft-security-updates",
  "document_id": 25488,
  "published_at": "2026-10-13T14:00:00+00:00"
}