{
  "fix": "KB5000848",
  "url": "https://patchblox.com/security/fix/microsoft/kb5000848",
  "summary": "KB5000848, released March 9, 2021, fixes 28 CVEs across 9 products. One of them is being exploited (CVE-2021-26411); 1 on CISA KEV. Patch Radar priority: Patch now.",
  "platform": "microsoft",
  "type": "kb",
  "releaseKind": "Security",
  "title": "March 2021 security update",
  "released": "2021-03-09T14:00:00Z",
  "priority": "Patch now",
  "priorityTier": 1,
  "priorityReason": "Closes CVE-2021-26411, exploited (CISA KEV, ransomware)",
  "supported": true,
  "cveCount": 28,
  "exploitedCveCount": 1,
  "kevCveCount": 1,
  "ransomwareCveCount": 1,
  "maxEpss": 0.81667,
  "maxCvss": 9.8,
  "vendorAdvisory": "https://support.microsoft.com/help/5000848",
  "appliesTo": [
    {
      "product": "Internet Explorer 11 on Windows 8.1 for 32-bit systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/internet-explorer-11-on-windows-8.1-for-32-bit-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Internet Explorer 11 on Windows 8.1 for x64-based systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/internet-explorer-11-on-windows-8.1-for-x64-based-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Internet Explorer 11 on Windows RT 8.1",
      "productUrl": "https://patchblox.com/security/product/microsoft/internet-explorer-11-on-windows-rt-8.1",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Internet Explorer 11 on Windows Server 2012 R2",
      "productUrl": "https://patchblox.com/security/product/microsoft/internet-explorer-11-on-windows-server-2012-r2",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Windows 8.1 for 32-bit systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/windows-8.1-for-32-bit-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Windows 8.1 for x64-based systems",
      "productUrl": "https://patchblox.com/security/product/microsoft/windows-8.1-for-x64-based-systems",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Windows RT 8.1",
      "productUrl": "https://patchblox.com/security/product/microsoft/windows-rt-8.1",
      "fixedVersion": "",
      "supported": false
    },
    {
      "product": "Windows Server 2012 R2",
      "productUrl": "https://patchblox.com/security/product/microsoft/windows-server-2012-r2",
      "fixedVersion": "",
      "supported": true
    },
    {
      "product": "Windows Server 2012 R2 (Server Core installation)",
      "productUrl": "https://patchblox.com/security/product/microsoft/windows-server-2012-r2-server-core-installation",
      "fixedVersion": "",
      "supported": true
    }
  ],
  "cves": [
    {
      "cveId": "CVE-2021-26411",
      "url": "https://patchblox.com/security/cve/CVE-2021-26411",
      "title": "Internet Explorer Memory Corruption Vulnerability",
      "component": "Internet Explorer",
      "impact": "Remote Code Execution",
      "priority": "Patch now",
      "severity": "Critical",
      "cvss": 8.8,
      "epss": 0.81667,
      "kev": true,
      "ransomware": true,
      "exploited": true,
      "disclosed": true
    },
    {
      "cveId": "CVE-2021-26877",
      "url": "https://patchblox.com/security/cve/CVE-2021-26877",
      "title": "Windows DNS Server Remote Code Execution Vulnerability",
      "component": "Role: DNS Server",
      "impact": "Remote Code Execution",
      "priority": "Urgent",
      "severity": "Important",
      "cvss": 9.8,
      "epss": 0.17285,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26897",
      "url": "https://patchblox.com/security/cve/CVE-2021-26897",
      "title": "Windows DNS Server Remote Code Execution Vulnerability",
      "component": "Role: DNS Server",
      "impact": "Remote Code Execution",
      "priority": "Urgent",
      "severity": "Critical",
      "cvss": 9.8,
      "epss": 0.11639,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26868",
      "url": "https://patchblox.com/security/cve/CVE-2021-26868",
      "title": "Windows Graphics Component Elevation of Privilege Vulnerability",
      "component": "Microsoft Graphics Component",
      "impact": "Elevation of Privilege",
      "priority": "Urgent",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.0308,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26896",
      "url": "https://patchblox.com/security/cve/CVE-2021-26896",
      "title": "Windows DNS Server Denial of Service Vulnerability",
      "component": "Role: DNS Server",
      "impact": "Denial of Service",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.5,
      "epss": 0.07846,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26894",
      "url": "https://patchblox.com/security/cve/CVE-2021-26894",
      "title": "Windows DNS Server Remote Code Execution Vulnerability",
      "component": "Role: DNS Server",
      "impact": "Remote Code Execution",
      "priority": "High",
      "severity": "Important",
      "cvss": 9.8,
      "epss": 0.07755,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26895",
      "url": "https://patchblox.com/security/cve/CVE-2021-26895",
      "title": "Windows DNS Server Remote Code Execution Vulnerability",
      "component": "Role: DNS Server",
      "impact": "Remote Code Execution",
      "priority": "High",
      "severity": "Important",
      "cvss": 9.8,
      "epss": 0.07755,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26893",
      "url": "https://patchblox.com/security/cve/CVE-2021-26893",
      "title": "Windows DNS Server Remote Code Execution Vulnerability",
      "component": "Role: DNS Server",
      "impact": "Remote Code Execution",
      "priority": "High",
      "severity": "Important",
      "cvss": 9.8,
      "epss": 0.0702,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-27063",
      "url": "https://patchblox.com/security/cve/CVE-2021-27063",
      "title": "Windows DNS Server Denial of Service Vulnerability",
      "component": "Role: DNS Server",
      "impact": "Denial of Service",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.5,
      "epss": 0.06727,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26879",
      "url": "https://patchblox.com/security/cve/CVE-2021-26879",
      "title": "Windows Network Address Translation (NAT) Denial of Service Vulnerability",
      "component": "Role: Windows Hyper-V",
      "impact": "Denial of Service",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.5,
      "epss": 0.03873,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26861",
      "url": "https://patchblox.com/security/cve/CVE-2021-26861",
      "title": "Windows Graphics Component Remote Code Execution Vulnerability",
      "component": "Microsoft Graphics Component",
      "impact": "Remote Code Execution",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.02888,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26881",
      "url": "https://patchblox.com/security/cve/CVE-2021-26881",
      "title": "Microsoft Windows Media Foundation Remote Code Execution Vulnerability",
      "component": "Windows Media",
      "impact": "Remote Code Execution",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.5,
      "epss": 0.02827,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26882",
      "url": "https://patchblox.com/security/cve/CVE-2021-26882",
      "title": "Remote Access API Elevation of Privilege Vulnerability",
      "component": "Windows Remote Access API",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.02106,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-27077",
      "url": "https://patchblox.com/security/cve/CVE-2021-27077",
      "title": "Windows Win32k Elevation of Privilege Vulnerability",
      "component": "Microsoft Graphics Component",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.01441,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": true
    },
    {
      "cveId": "CVE-2021-26862",
      "url": "https://patchblox.com/security/cve/CVE-2021-26862",
      "title": "Windows Installer Elevation of Privilege Vulnerability",
      "component": "Windows Installer",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7,
      "epss": 0.01248,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26873",
      "url": "https://patchblox.com/security/cve/CVE-2021-26873",
      "title": "Windows User Profile Service Elevation of Privilege Vulnerability",
      "component": "Windows User Profile Service",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7,
      "epss": 0.01149,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26899",
      "url": "https://patchblox.com/security/cve/CVE-2021-26899",
      "title": "Windows UPnP Device Host Elevation of Privilege Vulnerability",
      "component": "Windows UPnP Device Host",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.00965,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-1640",
      "url": "https://patchblox.com/security/cve/CVE-2021-1640",
      "title": "Windows Print Spooler Elevation of Privilege Vulnerability",
      "component": "Windows Print Spooler Components",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.00953,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26898",
      "url": "https://patchblox.com/security/cve/CVE-2021-26898",
      "title": "Windows Event Tracing Elevation of Privilege Vulnerability",
      "component": "Windows Event Tracing",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.00873,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26875",
      "url": "https://patchblox.com/security/cve/CVE-2021-26875",
      "title": "Windows Win32k Elevation of Privilege Vulnerability",
      "component": "Microsoft Graphics Component",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.00865,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26878",
      "url": "https://patchblox.com/security/cve/CVE-2021-26878",
      "title": "Windows Print Spooler Elevation of Privilege Vulnerability",
      "component": "Windows Print Spooler Components",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.00853,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26901",
      "url": "https://patchblox.com/security/cve/CVE-2021-26901",
      "title": "Windows Event Tracing Elevation of Privilege Vulnerability",
      "component": "Windows Event Tracing",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.00815,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26872",
      "url": "https://patchblox.com/security/cve/CVE-2021-26872",
      "title": "Windows Event Tracing Elevation of Privilege Vulnerability",
      "component": "Windows Event Tracing",
      "impact": "Elevation of Privilege",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.8,
      "epss": 0.00747,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2020-16996",
      "url": "https://patchblox.com/security/cve/CVE-2020-16996",
      "title": "Kerberos Security Feature Bypass Vulnerability",
      "component": "Microsoft Windows",
      "impact": "Security Feature Bypass",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 6.5,
      "epss": 0.0237,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26886",
      "url": "https://patchblox.com/security/cve/CVE-2021-26886",
      "title": "User Profile Service Denial of Service Vulnerability",
      "component": "Windows User Profile Service",
      "impact": "Denial of Service",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 6.1,
      "epss": 0.01133,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-24107",
      "url": "https://patchblox.com/security/cve/CVE-2021-24107",
      "title": "Windows Event Tracing Information Disclosure Vulnerability",
      "component": "Windows Event Tracing",
      "impact": "Information Disclosure",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 5.5,
      "epss": 0.01032,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26869",
      "url": "https://patchblox.com/security/cve/CVE-2021-26869",
      "title": "Windows ActiveX Installer Service Information Disclosure Vulnerability",
      "component": "Microsoft ActiveX",
      "impact": "Information Disclosure",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 5.5,
      "epss": 0.01032,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26884",
      "url": "https://patchblox.com/security/cve/CVE-2021-26884",
      "title": "Windows Media Photo Codec Information Disclosure Vulnerability",
      "component": "Microsoft Windows Codecs Library",
      "impact": "Information Disclosure",
      "priority": "Routine",
      "severity": "Important",
      "cvss": 5.5,
      "epss": 0.01032,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    }
  ],
  "dataAsOf": "2026-11-07T06:34:28Z"
}