{
  "id": "CVE-2021-40449",
  "url": "https://spydr.io/cve/CVE-2021-40449",
  "published": "2021-10-13T01:15:09.703Z",
  "modified": "2026-06-17T04:06:56.427Z",
  "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": 0.74129,
  "epss_percentile": 0.99477,
  "exploited": true,
  "kev": {
    "added": "2021-11-17",
    "due": "2021-12-01",
    "action": "Apply updates per vendor instructions.",
    "ransomware": "Known",
    "name": "Microsoft Windows Win32k Privilege Escalation Vulnerability",
    "notes": "https://nvd.nist.gov/vuln/detail/CVE-2021-40449"
  },
  "ssvc_exploitation": "active",
  "vendors": [
    "Microsoft"
  ],
  "products": [
    "Microsoft Windows 10 Version 1809",
    "Microsoft Windows Server 2019",
    "Microsoft Windows Server 2019 (Server Core installation)",
    "Microsoft Windows 10 Version 1909",
    "Microsoft Windows 10 Version 21H1",
    "Microsoft Windows Server 2022",
    "Microsoft Windows 10 Version 2004",
    "Microsoft Windows Server version 2004",
    "Microsoft Windows 10 Version 20H2",
    "Microsoft Windows Server version 20H2",
    "Microsoft Windows 11 version 21H2",
    "Microsoft Windows 10 Version 1507",
    "Microsoft Windows 10 Version 1607",
    "Microsoft Windows Server 2016",
    "Microsoft Windows Server 2016 (Server Core installation)",
    "Microsoft Windows 7",
    "Microsoft Windows 7 Service Pack 1",
    "Microsoft Windows 8.1",
    "Microsoft Windows Server 2008 Service Pack 2",
    "Microsoft Windows Server 2008 Service Pack 2 (Server Core installation)"
  ],
  "cwes": [
    "CWE-416"
  ],
  "description": "Win32k Elevation of Privilege Vulnerability",
  "status": "Analyzed",
  "score_type": "Secondary",
  "scores": {
    "cvss_v40": null,
    "cvss_v31": 7.8,
    "cvss_v30": null
  },
  "references": [
    {
      "url": "http://packetstormsecurity.com/files/164926/Win32k-NtGdiResetDC-Use-After-Free-Local-Privilege-Escalation.html",
      "tags": [
        "Exploit",
        "Third Party Advisory",
        "VDB Entry"
      ]
    },
    {
      "url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40449",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-40449",
      "tags": [
        "US Government Resource"
      ]
    }
  ],
  "nvd_url": "https://nvd.nist.gov/vuln/detail/CVE-2021-40449",
  "covered_in": [],
  "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."
    }
  ]
}