{
  "id": "CVE-2026-81963",
  "url": "https://spydr.io/cve/CVE-2026-81963",
  "published": "2026-09-08T18:21:00.090Z",
  "modified": "2026-09-09T05:18:17.173Z",
  "score": 7.8,
  "severity": "high",
  "cvss_version": "3.1",
  "vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
  "score_source": "microsoft.com",
  "epss": 0.00393,
  "epss_percentile": 0.31187,
  "exploited": true,
  "kev": {
    "added": "2026-09-08",
    "due": "2026-09-22",
    "action": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
    "ransomware": "Unknown",
    "name": "Microsoft Windows Link Following Vulnerability",
    "notes": "https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-81963 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-81963"
  },
  "ssvc_exploitation": "active",
  "vendors": [
    "Microsoft"
  ],
  "products": [
    "Microsoft Windows 11 version 23H2",
    "Microsoft Windows 11 Version 24H2",
    "Microsoft Windows 11 Version 25H2",
    "Microsoft Windows 11 version 26H1",
    "Microsoft Windows Server 2025",
    "Microsoft Windows Server 2025 (Server Core installation)"
  ],
  "cwes": [
    "CWE-59",
    "CWE-284"
  ],
  "description": "Improper link resolution before file access ('link following') in Windows Update Stack allows an authorized attacker to elevate privileges locally.",
  "status": "Analyzed",
  "score_type": "Secondary",
  "scores": {
    "cvss_v40": null,
    "cvss_v31": 7.8,
    "cvss_v30": null
  },
  "references": [
    {
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-81963",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-81963",
      "tags": [
        "US Government Resource"
      ]
    }
  ],
  "nvd_url": "https://nvd.nist.gov/vuln/detail/CVE-2026-81963",
  "covered_in": [
    {
      "title": "You thought patching was bad before?",
      "url": "https://www.securityskim.com/p/tech-revolution",
      "source": "skim",
      "published": "2026-09-10T14:25:01.000Z"
    }
  ],
  "attribution": [
    {
      "source": "NVD",
      "url": "https://nvd.nist.gov",
      "notice": "This product uses data from the NVD API but is not endorsed or certified by the NVD."
    },
    {
      "source": "CISA KEV",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "notice": "Known exploited vulnerabilities from the CISA KEV catalog."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss",
      "notice": "Exploit prediction scores from FIRST EPSS."
    }
  ]
}