{
  "fix": "KB5003173",
  "url": "https://patchblox.com/security/fix/microsoft/kb5003173",
  "summary": "KB5003173, released May 11, 2021, fixes 25 CVEs across 12 products. One of them is being exploited (CVE-2021-31166); 1 on CISA KEV. Patch Radar priority: Patch now. The product is no longer supported.",
  "platform": "microsoft",
  "type": "kb",
  "releaseKind": "Security",
  "title": "May 2021 cumulative update for Windows 10 2004",
  "released": "2021-05-11T00:00:00Z",
  "priority": "Patch now",
  "priorityTier": 1,
  "priorityReason": "Closes CVE-2021-31166, exploited (CISA KEV)",
  "supported": false,
  "cveCount": 25,
  "exploitedCveCount": 1,
  "kevCveCount": 1,
  "ransomwareCveCount": 0,
  "maxEpss": 0.99867,
  "maxCvss": 9.9,
  "vendorAdvisory": "https://support.microsoft.com/help/5003173",
  "appliesTo": [
    {
      "product": "Internet Explorer 11 on Windows 10 Version 2004 for 32-bit Systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/internet-explorer-11-on-windows-10-version-2004-for-32-bit-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Internet Explorer 11 on Windows 10 Version 2004 for ARM64-based Systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/internet-explorer-11-on-windows-10-version-2004-for-arm64-based-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Internet Explorer 11 on Windows 10 Version 2004 for x64-based Systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/internet-explorer-11-on-windows-10-version-2004-for-x64-based-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Internet Explorer 11 on Windows 10 Version 20H2 for 32-bit Systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/internet-explorer-11-on-windows-10-version-20h2-for-32-bit-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Internet Explorer 11 on Windows 10 Version 20H2 for ARM64-based Systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/internet-explorer-11-on-windows-10-version-20h2-for-arm64-based-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Windows 10 Version 2004 for 32-bit Systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/windows-10-version-2004-for-32-bit-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Windows 10 Version 2004 for ARM64-based Systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/windows-10-version-2004-for-arm64-based-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Windows 10 Version 2004 for x64-based Systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/windows-10-version-2004-for-x64-based-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Windows 10 Version 20H2 for 32-bit Systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/windows-10-version-20h2-for-32-bit-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Windows 10 Version 20H2 for ARM64-based Systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/windows-10-version-20h2-for-arm64-based-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Windows Server, version 2004 (Server Core installation)",
      "productUrl": "https://patchblox.com/security/product/microsoft/windows-server-version-2004-server-core-installation",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Windows Server, version 20H2 (Server Core Installation)",
      "productUrl": "https://patchblox.com/security/product/microsoft/windows-server-version-20h2-server-core-installation",
      "fixedVersion": "",
      "supported": false
    }
  ],
  "cves": [
    {
      "cveId": "CVE-2021-31166",
      "url": "https://patchblox.com/security/cve/CVE-2021-31166",
      "title": "HTTP Protocol Stack Remote Code Execution Vulnerability",
      "component": "Windows HTTP.sys",
      "impact": "Remote Code Execution",
      "priority": "Patch now",
      "severity": "Critical",
      "cvss": 9.8,
      "epss": 0.99867,
      "kev": true,
      "ransomware": false,
      "exploited": true,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-28476",
      "url": "https://patchblox.com/security/cve/CVE-2021-28476",
      "title": "Windows Hyper-V Remote Code Execution Vulnerability",
      "component": "Role: Windows Hyper-V",
      "impact": "Remote Code Execution",
      "priority": "Urgent",
      "severity": "Critical",
      "cvss": 9.9,
      "epss": 0.39226,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26419",
      "url": "https://patchblox.com/security/cve/CVE-2021-26419",
      "title": "Scripting Engine Memory Corruption Vulnerability",
      "component": "Internet Explorer",
      "impact": "Remote Code Execution",
      "priority": "Urgent",
      "severity": "Critical",
      "cvss": 6.4,
      "epss": 0.22767,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31194",
      "url": "https://patchblox.com/security/cve/CVE-2021-31194",
      "title": "OLE Automation Remote Code Execution Vulnerability",
      "component": "Windows OLE",
      "impact": "Remote Code Execution",
      "priority": "Urgent",
      "severity": "Critical",
      "cvss": 8.8,
      "epss": 0.02352,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31188",
      "url": "https://patchblox.com/security/cve/CVE-2021-31188",
      "title": "Windows Graphics Component Elevation of Privilege Vulnerability",
      "component": "Microsoft Graphics Component",
      "impact": "Elevation of Privilege",
      "priority": "Urgent",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.01368,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31170",
      "url": "https://patchblox.com/security/cve/CVE-2021-31170",
      "title": "Windows Graphics Component Elevation of Privilege Vulnerability",
      "component": "Microsoft Graphics Component",
      "impact": "Elevation of Privilege",
      "priority": "Urgent",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.0101,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31186",
      "url": "https://patchblox.com/security/cve/CVE-2021-31186",
      "title": "Windows Remote Desktop Protocol (RDP) Information Disclosure Vulnerability",
      "component": "Windows RDP Client",
      "impact": "Information Disclosure",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.4,
      "epss": 0.02966,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31192",
      "url": "https://patchblox.com/security/cve/CVE-2021-31192",
      "title": "Windows Media Foundation Core Remote Code Execution Vulnerability",
      "component": "Microsoft Windows Codecs Library",
      "impact": "Remote Code Execution",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.02253,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-28455",
      "url": "https://patchblox.com/security/cve/CVE-2021-28455",
      "title": "Microsoft Jet Red Database Engine and Access Connectivity Engine Remote Code Execution Vulnerability",
      "component": "Jet Red and Access Connectivity",
      "impact": "Remote Code Execution",
      "priority": "High",
      "severity": "Important",
      "cvss": 8.8,
      "epss": 0.0212,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31187",
      "url": "https://patchblox.com/security/cve/CVE-2021-31187",
      "title": "Windows WalletService Elevation of Privilege Vulnerability",
      "component": "Windows WalletService",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.01136,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31167",
      "url": "https://patchblox.com/security/cve/CVE-2021-31167",
      "title": "Windows Container Manager Service Elevation of Privilege Vulnerability",
      "component": "Windows Container Manager Service",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.01013,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31165",
      "url": "https://patchblox.com/security/cve/CVE-2021-31165",
      "title": "Windows Container Manager Service Elevation of Privilege Vulnerability",
      "component": "Windows Container Manager Service",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.00977,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31168",
      "url": "https://patchblox.com/security/cve/CVE-2021-31168",
      "title": "Windows Container Manager Service Elevation of Privilege Vulnerability",
      "component": "Windows Container Manager Service",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.00977,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31169",
      "url": "https://patchblox.com/security/cve/CVE-2021-31169",
      "title": "Windows Container Manager Service Elevation of Privilege Vulnerability",
      "component": "Windows Container Manager Service",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.00977,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31182",
      "url": "https://patchblox.com/security/cve/CVE-2021-31182",
      "title": "Microsoft Bluetooth Driver Spoofing Vulnerability",
      "component": "Microsoft Bluetooth Driver",
      "impact": "Spoofing",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.1,
      "epss": 0.00835,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31208",
      "url": "https://patchblox.com/security/cve/CVE-2021-31208",
      "title": "Windows Container Manager Service Elevation of Privilege Vulnerability",
      "component": "Windows Container Manager Service",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.00584,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31193",
      "url": "https://patchblox.com/security/cve/CVE-2021-31193",
      "title": "Windows SSDP Service Elevation of Privilege Vulnerability",
      "component": "Windows SSDP Service",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.00524,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2020-26144",
      "url": "https://patchblox.com/security/cve/CVE-2020-26144",
      "title": "Windows Wireless Networking Spoofing Vulnerability",
      "component": "Windows Wireless Networking",
      "impact": "Spoofing",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 6.5,
      "epss": 0.04913,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2020-24588",
      "url": "https://patchblox.com/security/cve/CVE-2020-24588",
      "title": "Windows Wireless Networking Spoofing Vulnerability",
      "component": "Windows Wireless Networking",
      "impact": "Spoofing",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 6.5,
      "epss": 0.03611,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31205",
      "url": "https://patchblox.com/security/cve/CVE-2021-31205",
      "title": "Windows SMB Client Security Feature Bypass Vulnerability",
      "component": "Windows SMB",
      "impact": "Security Feature Bypass",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 6.5,
      "epss": 0.02911,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2020-24587",
      "url": "https://patchblox.com/security/cve/CVE-2020-24587",
      "title": "Windows Wireless Networking Information Disclosure Vulnerability",
      "component": "Windows Wireless Networking",
      "impact": "Information Disclosure",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 6.5,
      "epss": 0.02592,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31184",
      "url": "https://patchblox.com/security/cve/CVE-2021-31184",
      "title": "Microsoft Windows Infrared Data Association (IrDA) Information Disclosure Vulnerability",
      "component": "Microsoft Windows IrDA",
      "impact": "Information Disclosure",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 5.5,
      "epss": 0.0156,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-28479",
      "url": "https://patchblox.com/security/cve/CVE-2021-28479",
      "title": "Windows CSC Service Information Disclosure Vulnerability",
      "component": "Windows CSC Service",
      "impact": "Information Disclosure",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 5.5,
      "epss": 0.0076,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31191",
      "url": "https://patchblox.com/security/cve/CVE-2021-31191",
      "title": "Windows Projected File System FS Filter Driver Information Disclosure Vulnerability",
      "component": "Windows Projected File System FS Filter",
      "impact": "Information Disclosure",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 5.5,
      "epss": 0.0076,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-31185",
      "url": "https://patchblox.com/security/cve/CVE-2021-31185",
      "title": "Windows Desktop Bridge Denial of Service Vulnerability",
      "component": "Windows Desktop Bridge",
      "impact": "Denial of Service",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 5.5,
      "epss": 0.00648,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    }
  ],
  "dataAsOf": "2026-11-07T12:40:37Z"
}