{
  "document": {
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "tlp": {
        "label": "WHITE"
      }
    },
    "lang": "nl",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this page to enhance access to its information and security advisories. The use of this security advisory is subject to the following terms and conditions:\n\n    NCSC-NL makes every reasonable effort to ensure that the content of this page is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or continuous keeping up-to-date. The information contained in this security advisory is intended solely for the purpose of providing general information to professional users. No rights can be derived from the information provided therein.\n\n    NCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of this security advisory. This includes damage resulting from the inaccuracy of incompleteness of the information contained in the advisory.\n    This security advisory is subject to Dutch law. All disputes related to or arising from the use of this advisory will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings."
      },
      {
        "category": "description",
        "text": "Microsoft heeft out-of-band, vooruitlopend op de maandelijkse update voor oktober, een kwetsbaarheid verholpen in Microsoft Exchange Server.",
        "title": "Feiten"
      },
      {
        "category": "description",
        "text": "De kwetsbaarheid betreft zwakke autorisatiecontroles binnen Microsoft Exchange Server. Een geauthenticeerde aanvaller kan hierdoor op afstand via het netwerk privileges escaleren. Dit betekent dat een aanvaller met geldige inloggegevens hogere rechten kan verkrijgen dan waarvoor deze geautoriseerd is, wat kan leiden tot ongeautoriseerde administratieve acties binnen de Exchange Server-omgeving.\n\nVoor Exchange Online zijn geen acties vereist. Microsoft heeft hiervoor centraal updates uitgerold. Deze kwetsbaarheid vereist wel actie voor organisaties die Exchange on premise hebben draaien.",
        "title": "Interpretaties"
      },
      {
        "category": "description",
        "text": "Microsoft heeft updates uitgebracht om de kwetsbaarheid te verhelpen. Zie bijgevoegde referenties voor meer informatie.",
        "title": "Oplossingen"
      },
      {
        "category": "general",
        "text": "medium",
        "title": "Kans"
      },
      {
        "category": "general",
        "text": "high",
        "title": "Schade"
      },
      {
        "category": "general",
        "text": "Weak Authentication",
        "title": "CWE-1390"
      }
    ],
    "publisher": {
      "category": "coordinator",
      "contact_details": "cert@ncsc.nl",
      "name": "Nationaal Cyber Security Centrum",
      "namespace": "https://www.ncsc.nl/"
    },
    "references": [
      {
        "category": "external",
        "summary": "Reference",
        "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-96940"
      }
    ],
    "title": "Kwetsbaarheid verholpen in Microsoft Exchange Server",
    "tracking": {
      "current_release_date": "2026-10-06T08:23:53.102568Z",
      "generator": {
        "date": "2025-08-04T16:30:00Z",
        "engine": {
          "name": "V.A.",
          "version": "1.3"
        }
      },
      "id": "NCSC-2026-0401",
      "initial_release_date": "2026-10-06T08:23:53.102568Z",
      "revision_history": [
        {
          "date": "2026-10-06T08:23:53.102568Z",
          "number": "1.0.0",
          "summary": "Initiele versie"
        }
      ],
      "status": "final",
      "version": "1.0.0"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:unknown/*",
                "product": {
                  "name": "vers:unknown/*",
                  "product_id": "CSAFPID-1"
                }
              }
            ],
            "category": "product_name",
            "name": "Microsoft Exchange Server 2016 Cumulative Update 23"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:unknown/*",
                "product": {
                  "name": "vers:unknown/*",
                  "product_id": "CSAFPID-2"
                }
              }
            ],
            "category": "product_name",
            "name": "Microsoft Exchange Server 2019 Cumulative Update 14"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:unknown/*",
                "product": {
                  "name": "vers:unknown/*",
                  "product_id": "CSAFPID-3"
                }
              }
            ],
            "category": "product_name",
            "name": "Microsoft Exchange Server 2019 Cumulative Update 15"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:unknown/*",
                "product": {
                  "name": "vers:unknown/*",
                  "product_id": "CSAFPID-4"
                }
              }
            ],
            "category": "product_name",
            "name": "Microsoft Exchange Server Subscription Edition RTM"
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-96940",
      "cwe": {
        "id": "CWE-1390",
        "name": "Weak Authentication"
      },
      "notes": [
        {
          "category": "other",
          "text": "Weak Authentication",
          "title": "CWE-1390"
        },
        {
          "category": "description",
          "text": "A weakness in authorization within Microsoft Exchange Server enables an authenticated attacker to escalate privileges remotely over a network.",
          "title": "Summary"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-1",
          "CSAFPID-2",
          "CSAFPID-3",
          "CSAFPID-4"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-96940 | NCSC-NL Website",
          "url": "https://vulnerabilities.ncsc.nl/csaf/v2/2026/cve-2026-96940.json"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 8.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-1",
            "CSAFPID-2",
            "CSAFPID-3",
            "CSAFPID-4"
          ]
        }
      ],
      "title": "CVE-2026-96940"
    }
  ]
}