{
  "document": {
    "acknowledgments": [
      {
        "names": [
          "<a href=\"https://www.linkedin.com/in/danielr1123/\">Daniel R</a>"
        ]
      }
    ],
    "aggregate_severity": {
      "namespace": "https://www.microsoft.com/en-us/msrc/security-update-severity-rating-system",
      "text": "Important"
    },
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Public",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "general",
        "text": "To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle",
        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
      },
      {
        "category": "general",
        "text": "Required. The vulnerability documented by this CVE requires customer action to resolve.",
        "title": "Customer Action"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "secure@microsoft.com",
      "name": "Microsoft Security Response Center",
      "namespace": "https://msrc.microsoft.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "CVE-2026-21530 Windows Rich Text Edit Elevation of Privilege Vulnerability - HTML",
        "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21530"
      },
      {
        "category": "self",
        "summary": "CVE-2026-21530 Windows Rich Text Edit Elevation of Privilege Vulnerability - CSAF",
        "url": "https://msrc.microsoft.com/csaf/advisories/2026/msrc_cve-2026-21530.json"
      },
      {
        "category": "external",
        "summary": "Microsoft Exploitability Index",
        "url": "https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1"
      },
      {
        "category": "external",
        "summary": "Microsoft Support Lifecycle",
        "url": "https://support.microsoft.com/lifecycle"
      },
      {
        "category": "external",
        "summary": "Common Vulnerability Scoring System",
        "url": "https://www.first.org/cvss"
      }
    ],
    "title": "Windows Rich Text Edit Elevation of Privilege Vulnerability",
    "tracking": {
      "current_release_date": "2026-06-09T07:00:00.000Z",
      "generator": {
        "date": "2026-06-09T19:32:20.302Z",
        "engine": {
          "name": "MSRC Generator",
          "version": "1.0"
        }
      },
      "id": "msrc_CVE-2026-21530",
      "initial_release_date": "2026-05-12T07:00:00.000Z",
      "revision_history": [
        {
          "date": "2026-05-12T07:00:00.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
        },
        {
          "date": "2026-05-15T07:00:00.000Z",
          "legacy_version": "1.1",
          "number": "2",
          "summary": "Updated Hotpatch links.  This is in informational change only."
        },
        {
          "date": "2026-06-09T07:00:00.000Z",
          "legacy_version": "2",
          "number": "3",
          "summary": "Added Office softwares to the Security Updates table. Customers that are running supported versions of Office are encouraged to update to the indicated versions to be protected from this vulnerability."
        }
      ],
      "status": "final",
      "version": "3"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.17763.8755",
            "product": {
              "name": "Windows 10 Version 1809 for 32-bit Systems <10.0.17763.8755",
              "product_id": "31"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.17763.8755",
            "product": {
              "name": "Windows 10 Version 1809 for 32-bit Systems 10.0.17763.8755",
              "product_id": "11568"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 10 Version 1809 for 32-bit Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.17763.8755",
            "product": {
              "name": "Windows 10 Version 1809 for x64-based Systems <10.0.17763.8755",
              "product_id": "30"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.17763.8755",
            "product": {
              "name": "Windows 10 Version 1809 for x64-based Systems 10.0.17763.8755",
              "product_id": "11569"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 10 Version 1809 for x64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.17763.8755",
            "product": {
              "name": "Windows Server 2019 <10.0.17763.8755",
              "product_id": "29"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.17763.8755",
            "product": {
              "name": "Windows Server 2019 10.0.17763.8755",
              "product_id": "11571"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2019"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.17763.8755",
            "product": {
              "name": "Windows Server 2019 (Server Core installation) <10.0.17763.8755",
              "product_id": "28"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.17763.8755",
            "product": {
              "name": "Windows Server 2019 (Server Core installation) 10.0.17763.8755",
              "product_id": "11572"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2019 (Server Core installation)"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.20348.5139",
            "product": {
              "name": "Windows Server 2022 <10.0.20348.5139",
              "product_id": "23"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.20348.5139",
            "product": {
              "name": "Windows Server 2022 10.0.20348.5139",
              "product_id": "11923"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2022"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.20348.5139",
            "product": {
              "name": "Windows Server 2022 (Server Core installation) <10.0.20348.5139",
              "product_id": "22"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.20348.5139",
            "product": {
              "name": "Windows Server 2022 (Server Core installation) 10.0.20348.5139",
              "product_id": "11924"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2022 (Server Core installation)"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.19044.7291",
            "product": {
              "name": "Windows 10 Version 21H2 for 32-bit Systems <10.0.19044.7291",
              "product_id": "21"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.19044.7291",
            "product": {
              "name": "Windows 10 Version 21H2 for 32-bit Systems 10.0.19044.7291",
              "product_id": "11929"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 10 Version 21H2 for 32-bit Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.19044.7291",
            "product": {
              "name": "Windows 10 Version 21H2 for ARM64-based Systems <10.0.19044.7291",
              "product_id": "20"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.19044.7291",
            "product": {
              "name": "Windows 10 Version 21H2 for ARM64-based Systems 10.0.19044.7291",
              "product_id": "11930"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 10 Version 21H2 for ARM64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.19044.7291",
            "product": {
              "name": "Windows 10 Version 21H2 for x64-based Systems <10.0.19044.7291",
              "product_id": "19"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.19044.7291",
            "product": {
              "name": "Windows 10 Version 21H2 for x64-based Systems 10.0.19044.7291",
              "product_id": "11931"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 10 Version 21H2 for x64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.19045.7417",
            "product": {
              "name": "Windows 10 Version 22H2 for x64-based Systems <10.0.19045.7417",
              "product_id": "16"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.19045.7417",
            "product": {
              "name": "Windows 10 Version 22H2 for x64-based Systems 10.0.19045.7417",
              "product_id": "12097"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 10 Version 22H2 for x64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.19045.7417",
            "product": {
              "name": "Windows 10 Version 22H2 for ARM64-based Systems <10.0.19045.7417",
              "product_id": "15"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.19045.7417",
            "product": {
              "name": "Windows 10 Version 22H2 for ARM64-based Systems 10.0.19045.7417",
              "product_id": "12098"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 10 Version 22H2 for ARM64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.19045.7417",
            "product": {
              "name": "Windows 10 Version 22H2 for 32-bit Systems <10.0.19045.7417",
              "product_id": "14"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.19045.7417",
            "product": {
              "name": "Windows 10 Version 22H2 for 32-bit Systems 10.0.19045.7417",
              "product_id": "12099"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 10 Version 22H2 for 32-bit Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.26100.32860",
            "product": {
              "name": "Windows Server 2025 (Server Core installation) <10.0.26100.32860",
              "product_id": "5"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.26100.32860",
            "product": {
              "name": "Windows Server 2025 (Server Core installation) 10.0.26100.32860",
              "product_id": "12437"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2025 (Server Core installation)"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.26200.8457",
            "product": {
              "name": "Windows 11 Version 25H2 for ARM64-based Systems <10.0.26200.8457",
              "product_id": "4"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.26200.8457",
            "product": {
              "name": "Windows 11 Version 25H2 for ARM64-based Systems 10.0.26200.8457",
              "product_id": "20437"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 11 Version 25H2 for ARM64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.26200.8457",
            "product": {
              "name": "Windows 11 Version 25H2 for x64-based Systems <10.0.26200.8457",
              "product_id": "3"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.26200.8457",
            "product": {
              "name": "Windows 11 Version 25H2 for x64-based Systems 10.0.26200.8457",
              "product_id": "20438"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 11 Version 25H2 for x64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.22631.7079",
            "product": {
              "name": "Windows 11 Version 23H2 for ARM64-based Systems <10.0.22631.7079",
              "product_id": "13"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.22631.7079",
            "product": {
              "name": "Windows 11 Version 23H2 for ARM64-based Systems 10.0.22631.7079",
              "product_id": "12242"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 11 Version 23H2 for ARM64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.22631.7219",
            "product": {
              "name": "Windows 11 Version 23H2 for x64-based Systems <10.0.22631.7219",
              "product_id": "12"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.22631.7219",
            "product": {
              "name": "Windows 11 Version 23H2 for x64-based Systems 10.0.22631.7219",
              "product_id": "12243"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 11 Version 23H2 for x64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.25398.2330",
            "product": {
              "name": "Windows Server 2022, 23H2 Edition (Server Core installation) <10.0.25398.2330",
              "product_id": "11"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.25398.2330",
            "product": {
              "name": "Windows Server 2022, 23H2 Edition (Server Core installation) 10.0.25398.2330",
              "product_id": "12244"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2022, 23H2 Edition (Server Core installation)"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.26100.8457",
            "product": {
              "name": "Windows 11 Version 24H2 for ARM64-based Systems <10.0.26100.8457",
              "product_id": "10"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.26100.8457",
            "product": {
              "name": "Windows 11 Version 24H2 for ARM64-based Systems 10.0.26100.8457",
              "product_id": "12389"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 11 Version 24H2 for ARM64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.26100.8457",
            "product": {
              "name": "Windows 11 Version 24H2 for x64-based Systems <10.0.26100.8457",
              "product_id": "9"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.26100.8457",
            "product": {
              "name": "Windows 11 Version 24H2 for x64-based Systems 10.0.26100.8457",
              "product_id": "12390"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 11 Version 24H2 for x64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.26100.32860",
            "product": {
              "name": "Windows Server 2025 <10.0.26100.32860",
              "product_id": "6"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.26100.32860",
            "product": {
              "name": "Windows Server 2025 10.0.26100.32860",
              "product_id": "12436"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2025"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.28000.2113",
            "product": {
              "name": "Windows 11 version 26H1 for x64-based Systems <10.0.28000.2113",
              "product_id": "2"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.28000.2113",
            "product": {
              "name": "Windows 11 version 26H1 for x64-based Systems 10.0.28000.2113",
              "product_id": "20853"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 11 version 26H1 for x64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.28000.2113",
            "product": {
              "name": "Windows 11 Version 26H1 for ARM64-based Systems <10.0.28000.2113",
              "product_id": "1"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.28000.2113",
            "product": {
              "name": "Windows 11 Version 26H1 for ARM64-based Systems 10.0.28000.2113",
              "product_id": "20854"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 11 Version 26H1 for ARM64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.14393.9140",
            "product": {
              "name": "Windows 10 Version 1607 for 32-bit Systems <10.0.14393.9140",
              "product_id": "34"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.14393.9140",
            "product": {
              "name": "Windows 10 Version 1607 for 32-bit Systems 10.0.14393.9140",
              "product_id": "10852"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 10 Version 1607 for 32-bit Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.14393.9140",
            "product": {
              "name": "Windows 10 Version 1607 for x64-based Systems <10.0.14393.9140",
              "product_id": "33"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.14393.9140",
            "product": {
              "name": "Windows 10 Version 1607 for x64-based Systems 10.0.14393.9140",
              "product_id": "10853"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows 10 Version 1607 for x64-based Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.14393.9140",
            "product": {
              "name": "Windows Server 2016 <10.0.14393.9140",
              "product_id": "35"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.14393.9140",
            "product": {
              "name": "Windows Server 2016 10.0.14393.9140",
              "product_id": "10816"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2016"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<10.0.14393.9140",
            "product": {
              "name": "Windows Server 2016 (Server Core installation) <10.0.14393.9140",
              "product_id": "32"
            }
          },
          {
            "category": "product_version",
            "name": "10.0.14393.9140",
            "product": {
              "name": "Windows Server 2016 (Server Core installation) 10.0.14393.9140",
              "product_id": "10855"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2016 (Server Core installation)"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<6.2.9200.26079",
            "product": {
              "name": "Windows Server 2012 <6.2.9200.26079",
              "product_id": "41"
            }
          },
          {
            "category": "product_version",
            "name": "6.2.9200.26079",
            "product": {
              "name": "Windows Server 2012 6.2.9200.26079",
              "product_id": "10378"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2012"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<6.2.9200.26079",
            "product": {
              "name": "Windows Server 2012 (Server Core installation) <6.2.9200.26079",
              "product_id": "40"
            }
          },
          {
            "category": "product_version",
            "name": "6.2.9200.26079",
            "product": {
              "name": "Windows Server 2012 (Server Core installation) 6.2.9200.26079",
              "product_id": "10379"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2012 (Server Core installation)"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<6.3.9600.23181",
            "product": {
              "name": "Windows Server 2012 R2 <6.3.9600.23181",
              "product_id": "39"
            }
          },
          {
            "category": "product_version",
            "name": "6.3.9600.23181",
            "product": {
              "name": "Windows Server 2012 R2 6.3.9600.23181",
              "product_id": "10483"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2012 R2"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<6.3.9600.23181",
            "product": {
              "name": "Windows Server 2012 R2 (Server Core installation) <6.3.9600.23181",
              "product_id": "38"
            }
          },
          {
            "category": "product_version",
            "name": "6.3.9600.23181",
            "product": {
              "name": "Windows Server 2012 R2 (Server Core installation) 6.3.9600.23181",
              "product_id": "10543"
            }
          }
        ],
        "category": "product_name",
        "name": "Windows Server 2012 R2 (Server Core installation)"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft Office 2019 for 32-bit editions <https://aka.ms/OfficeSecurityReleases",
              "product_id": "27"
            }
          },
          {
            "category": "product_version",
            "name": "https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft Office 2019 for 32-bit editions https://aka.ms/OfficeSecurityReleases",
              "product_id": "11573"
            }
          }
        ],
        "category": "product_name",
        "name": "Microsoft Office 2019 for 32-bit editions"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft Office 2019 for 64-bit editions <https://aka.ms/OfficeSecurityReleases",
              "product_id": "26"
            }
          },
          {
            "category": "product_version",
            "name": "https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft Office 2019 for 64-bit editions https://aka.ms/OfficeSecurityReleases",
              "product_id": "11574"
            }
          }
        ],
        "category": "product_name",
        "name": "Microsoft Office 2019 for 64-bit editions"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft 365 Apps for Enterprise for 32-bit Systems <https://aka.ms/OfficeSecurityReleases",
              "product_id": "25"
            }
          },
          {
            "category": "product_version",
            "name": "https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft 365 Apps for Enterprise for 32-bit Systems https://aka.ms/OfficeSecurityReleases",
              "product_id": "11762"
            }
          }
        ],
        "category": "product_name",
        "name": "Microsoft 365 Apps for Enterprise for 32-bit Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft 365 Apps for Enterprise for 64-bit Systems <https://aka.ms/OfficeSecurityReleases",
              "product_id": "24"
            }
          },
          {
            "category": "product_version",
            "name": "https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft 365 Apps for Enterprise for 64-bit Systems https://aka.ms/OfficeSecurityReleases",
              "product_id": "11763"
            }
          }
        ],
        "category": "product_name",
        "name": "Microsoft 365 Apps for Enterprise for 64-bit Systems"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft Office LTSC 2021 for 64-bit editions <https://aka.ms/OfficeSecurityReleases",
              "product_id": "18"
            }
          },
          {
            "category": "product_version",
            "name": "https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft Office LTSC 2021 for 64-bit editions https://aka.ms/OfficeSecurityReleases",
              "product_id": "11952"
            }
          }
        ],
        "category": "product_name",
        "name": "Microsoft Office LTSC 2021 for 64-bit editions"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft Office LTSC 2021 for 32-bit editions <https://aka.ms/OfficeSecurityReleases",
              "product_id": "17"
            }
          },
          {
            "category": "product_version",
            "name": "https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft Office LTSC 2021 for 32-bit editions https://aka.ms/OfficeSecurityReleases",
              "product_id": "11953"
            }
          }
        ],
        "category": "product_name",
        "name": "Microsoft Office LTSC 2021 for 32-bit editions"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft Office LTSC 2024 for 32-bit editions <https://aka.ms/OfficeSecurityReleases",
              "product_id": "8"
            }
          },
          {
            "category": "product_version",
            "name": "https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft Office LTSC 2024 for 32-bit editions https://aka.ms/OfficeSecurityReleases",
              "product_id": "12420"
            }
          }
        ],
        "category": "product_name",
        "name": "Microsoft Office LTSC 2024 for 32-bit editions"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft Office LTSC 2024 for 64-bit editions <https://aka.ms/OfficeSecurityReleases",
              "product_id": "7"
            }
          },
          {
            "category": "product_version",
            "name": "https://aka.ms/OfficeSecurityReleases",
            "product": {
              "name": "Microsoft Office LTSC 2024 for 64-bit editions https://aka.ms/OfficeSecurityReleases",
              "product_id": "12421"
            }
          }
        ],
        "category": "product_name",
        "name": "Microsoft Office LTSC 2024 for 64-bit editions"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<16.0.5556.1000",
            "product": {
              "name": "Microsoft Office 2016 (32-bit edition) <16.0.5556.1000",
              "product_id": "37"
            }
          },
          {
            "category": "product_version",
            "name": "16.0.5556.1000",
            "product": {
              "name": "Microsoft Office 2016 (32-bit edition) 16.0.5556.1000",
              "product_id": "10753"
            }
          }
        ],
        "category": "product_name",
        "name": "Microsoft Office 2016 (32-bit edition)"
      },
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "<16.0.5556.1000",
            "product": {
              "name": "Microsoft Office 2016 (64-bit edition) <16.0.5556.1000",
              "product_id": "36"
            }
          },
          {
            "category": "product_version",
            "name": "16.0.5556.1000",
            "product": {
              "name": "Microsoft Office 2016 (64-bit edition) 16.0.5556.1000",
              "product_id": "10754"
            }
          }
        ],
        "category": "product_name",
        "name": "Microsoft Office 2016 (64-bit edition)"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-21530",
      "cwe": {
        "id": "CWE-415",
        "name": "Double Free"
      },
      "notes": [
        {
          "category": "general",
          "text": "Microsoft",
          "title": "Assigning CNA"
        },
        {
          "category": "faq",
          "text": "An attacker who successfully exploited this vulnerability could gain administrator privileges.",
          "title": "What privileges could be gained by an attacker who successfully exploited the vulnerability?"
        },
        {
          "category": "faq",
          "text": "Successful exploitation of this vulnerability requires an attacker to win a race condition.",
          "title": "According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability?"
        },
        {
          "category": "faq",
          "text": "An authorized attacker must send a victim a malicious and specially crafted file and convince them to open it.",
          "title": "According to the CVSS metric, user interaction is required (UI:R) and privileges required is Low (PR:L). What does that mean for this vulnerability?"
        }
      ],
      "product_status": {
        "fixed": [
          "10378",
          "10379",
          "10483",
          "10543",
          "10753",
          "10754",
          "10816",
          "10852",
          "10853",
          "10855",
          "11568",
          "11569",
          "11571",
          "11572",
          "11573",
          "11574",
          "11762",
          "11763",
          "11923",
          "11924",
          "11929",
          "11930",
          "11931",
          "11952",
          "11953",
          "12097",
          "12098",
          "12099",
          "12242",
          "12243",
          "12244",
          "12389",
          "12390",
          "12420",
          "12421",
          "12436",
          "12437",
          "20437",
          "20438",
          "20853",
          "20854"
        ],
        "known_affected": [
          "1",
          "2",
          "3",
          "4",
          "5",
          "6",
          "7",
          "8",
          "9",
          "10",
          "11",
          "12",
          "13",
          "14",
          "15",
          "16",
          "17",
          "18",
          "19",
          "20",
          "21",
          "22",
          "23",
          "24",
          "25",
          "26",
          "27",
          "28",
          "29",
          "30",
          "31",
          "32",
          "33",
          "34",
          "35",
          "36",
          "37",
          "38",
          "39",
          "40",
          "41"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-21530 Windows Rich Text Edit Elevation of Privilege Vulnerability - HTML",
          "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21530"
        },
        {
          "category": "self",
          "summary": "CVE-2026-21530 Windows Rich Text Edit Elevation of Privilege Vulnerability - CSAF",
          "url": "https://msrc.microsoft.com/csaf/advisories/2026/msrc_cve-2026-21530.json"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.17763.8755:Security Update:https://support.microsoft.com/help/5087538",
          "product_ids": [
            "31",
            "30",
            "29",
            "28"
          ],
          "url": "https://support.microsoft.com/help/5087538"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.20348.5139:Security Update:https://support.microsoft.com/help/5087545",
          "product_ids": [
            "23",
            "22"
          ],
          "url": "https://support.microsoft.com/help/5087545"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.20348.5074:Security Hotpatch Update:https://support.microsoft.com/help/5087424",
          "product_ids": [
            "23",
            "22"
          ],
          "url": "https://support.microsoft.com/help/5087424"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.19044.7291:Security Update:https://support.microsoft.com/help/5087544",
          "product_ids": [
            "21",
            "20",
            "19"
          ],
          "url": "https://support.microsoft.com/help/5087544"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.19045.7417:Security Update:https://support.microsoft.com/help/5094127",
          "product_ids": [
            "16",
            "15",
            "14"
          ],
          "url": "https://support.microsoft.com/help/5094127"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.26100.32860:Security Update:https://support.microsoft.com/help/5087539",
          "product_ids": [
            "5",
            "6"
          ],
          "url": "https://support.microsoft.com/help/5087539"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.26100.32772:Security Hotpatch Update:https://support.microsoft.com/help/5087423",
          "product_ids": [
            "5",
            "6"
          ],
          "url": "https://support.microsoft.com/help/5087423"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.26200.8457:Security Update:https://support.microsoft.com/help/5089549",
          "product_ids": [
            "4",
            "3"
          ],
          "url": "https://support.microsoft.com/help/5089549"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.26200.8390:Security Hotpatch Update:https://support.microsoft.com/help/5089466",
          "product_ids": [
            "4",
            "3"
          ],
          "url": "https://support.microsoft.com/help/5089466"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.22631.7079:Security Update:https://support.microsoft.com/help/5087420",
          "product_ids": [
            "13"
          ],
          "url": "https://support.microsoft.com/help/5087420"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.22631.7219:Security Update:https://support.microsoft.com/help/5093998",
          "product_ids": [
            "12"
          ],
          "url": "https://support.microsoft.com/help/5093998"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.25398.2330:Security Update:https://support.microsoft.com/help/5087541",
          "product_ids": [
            "11"
          ],
          "url": "https://support.microsoft.com/help/5087541"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.26100.8457:Security Update:https://support.microsoft.com/help/5089549",
          "product_ids": [
            "10",
            "9"
          ],
          "url": "https://support.microsoft.com/help/5089549"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.26100.8390:Security Hotpatch Update:https://support.microsoft.com/help/5089466",
          "product_ids": [
            "10",
            "9"
          ],
          "url": "https://support.microsoft.com/help/5089466"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.28000.2113:Security Update:https://support.microsoft.com/help/5089548",
          "product_ids": [
            "2",
            "1"
          ],
          "url": "https://support.microsoft.com/help/5089548"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "10.0.14393.9140:Security Update:https://support.microsoft.com/help/5087537",
          "product_ids": [
            "34",
            "33",
            "35",
            "32"
          ],
          "url": "https://support.microsoft.com/help/5087537"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "6.2.9200.26079:Monthly Rollup:https://support.microsoft.com/help/5087470",
          "product_ids": [
            "41",
            "40"
          ],
          "url": "https://support.microsoft.com/help/5087470"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "6.3.9600.23181:Monthly Rollup:https://support.microsoft.com/help/5087471",
          "product_ids": [
            "39",
            "38"
          ],
          "url": "https://support.microsoft.com/help/5087471"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "https://aka.ms/OfficeSecurityReleases:Security Update:https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates",
          "product_ids": [
            "27",
            "26",
            "25",
            "24",
            "18",
            "17",
            "8",
            "7"
          ],
          "url": "https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates"
        },
        {
          "category": "vendor_fix",
          "date": "2026-05-12T07:00:00.000Z",
          "details": "16.0.5556.1000:Security Update:https://support.microsoft.com/help/5002578",
          "product_ids": [
            "37",
            "36"
          ],
          "url": "https://support.microsoft.com/help/5002578"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 6.7,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "environmentalsScore": 0.0,
            "exploitCodeMaturity": "UNPROVEN",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "remediationLevel": "OFFICIAL_FIX",
            "reportConfidence": "CONFIRMED",
            "scope": "UNCHANGED",
            "temporalScore": 5.8,
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C",
            "version": "3.1"
          },
          "products": [
            "1",
            "2",
            "3",
            "4",
            "5",
            "6",
            "7",
            "8",
            "9",
            "10",
            "11",
            "12",
            "13",
            "14",
            "15",
            "16",
            "17",
            "18",
            "19",
            "20",
            "21",
            "22",
            "23",
            "24",
            "25",
            "26",
            "27",
            "28",
            "29",
            "30",
            "31",
            "32",
            "33",
            "34",
            "35",
            "36",
            "37",
            "38",
            "39",
            "40",
            "41"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "details": "Elevation of Privilege"
        },
        {
          "category": "exploit_status",
          "details": "Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely"
        }
      ],
      "title": "Windows Rich Text Edit Elevation of Privilege Vulnerability"
    }
  ]
}