{
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    "category": "csaf_vex",
    "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"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "secure@microsoft.com",
      "name": "Microsoft Security Response Center",
      "namespace": "https://msrc.microsoft.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "CVE-2026-78450 Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability - VEX",
        "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-78450.json"
      },
      {
        "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 Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability",
    "tracking": {
      "current_release_date": "2026-09-08T07:00:00.000Z",
      "generator": {
        "date": "2026-10-07T14:56:01.721Z",
        "engine": {
          "name": "MSRC Generator",
          "version": "1.0"
        }
      },
      "id": "msrc_CVE-2026-78450",
      "initial_release_date": "2026-09-08T07:00:00.000Z",
      "revision_history": [
        {
          "date": "2026-09-08T07:00:00.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
        }
      ],
      "status": "final",
      "version": "1"
    }
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                "name": "10.0.17763.9245",
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              },
              {
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                  "product_id": "12436"
                }
              }
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            "name": "Windows Server 2025"
          }
        ],
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        "name": "Microsoft"
      }
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  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-78450",
      "cwe": {
        "id": "CWE-416",
        "name": "Use After Free"
      },
      "notes": [
        {
          "category": "general",
          "text": "Microsoft",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
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          "11569",
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          "6",
          "5",
          "4",
          "3",
          "1",
          "2"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-78450 Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability - VEX",
          "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-78450.json"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "date": "2026-09-08T07:00:00.000Z",
          "details": "10.0.17763.9245:Security Update:https://support.microsoft.com/help/5122876",
          "product_ids": [
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            "7",
            "6",
            "5"
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          "url": "https://support.microsoft.com/help/5122876"
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        {
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          "date": "2026-09-08T07:00:00.000Z",
          "details": "10.0.20348.5622:Security Update:https://support.microsoft.com/help/5122882",
          "product_ids": [
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            "3"
          ],
          "url": "https://support.microsoft.com/help/5122882"
        },
        {
          "category": "vendor_fix",
          "date": "2026-09-08T07:00:00.000Z",
          "details": "10.0.26100.33438:Security Update:https://support.microsoft.com/help/5122871",
          "product_ids": [
            "1",
            "2"
          ],
          "url": "https://support.microsoft.com/help/5122871"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 8.1,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "exploitCodeMaturity": "UNPROVEN",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "remediationLevel": "OFFICIAL_FIX",
            "reportConfidence": "CONFIRMED",
            "scope": "UNCHANGED",
            "temporalScore": 7.1,
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/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"
          ]
        }
      ],
      "title": "Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability"
    }
  ]
}