Vulnerability-Lookup

WID-SEC-W-2026-3718

Vulnerability from csaf_certbund - Published: 2026-10-04 22:00 - Updated: 2026-10-04 22:00

Summary

Microsoft Exchange Server: Schwachstelle ermöglicht Privilegieneskalation

Severity

Hoch

Notes

Das BSI ist als Anbieter für die eigenen, zur Nutzung bereitgestellten Inhalte nach den allgemeinen Gesetzen verantwortlich. Nutzerinnen und Nutzer sind jedoch dafür verantwortlich, die Verwendung und/oder die Umsetzung der mit den Inhalten bereitgestellten Informationen sorgfältig im Einzelfall zu prüfen.

Produktbeschreibung: Exchange ist ein Groupware und Nachrichtensystem der Firma Microsoft.

Angriff: Ein entfernter, authentisierter Angreifer kann eine Schwachstelle in Microsoft Exchange Server ausnutzen, um seine Privilegien zu erhöhen, wodurch er Zugriff auf die Postfächer anderer Benutzer innerhalb derselben Organisation erhält und E-Mail-Nachrichten sowie Anhänge lesen kann.

Betroffene Betriebssysteme: - Windows

CVE-2026-96940

Affected products

Known affected 4 products

Product	Identifier	Version
Microsoft Exchange Server 2016 Cumulative Update 23 Microsoft / Exchange	`cpe:/a:microsoft:exchange:server_2016_cumulative_update_23`	Server 2016 Cumulative Update 23
Microsoft Exchange Server Subscription Edition RTM Microsoft / Exchange	`cpe:/a:microsoft:exchange:server_subscription_edition_rtm`	Server Subscription Edition RTM
Microsoft Exchange Server 2019 Cumulative Update 14 Microsoft / Exchange	`cpe:/a:microsoft:exchange:server_2019_cumulative_update_14`	Server 2019 Cumulative Update 14
Microsoft Exchange Server 2019 Cumulative Update 15 Microsoft / Exchange	`cpe:/a:microsoft:exchange:server_2019_cumulative_update_15`	Server 2019 Cumulative Update 15

References

3 references

URL	Category
https://wid.cert-bund.de/.well-known/csaf/white/2…	self
https://wid.cert-bund.de/portal/wid/securityadvis…	self
https://msrc.microsoft.com/update-guide/vulnerabi…	external

JSON

To clipboard

{
  "document": {
    "aggregate_severity": {
      "text": "hoch"
    },
    "category": "csaf_base",
    "csaf_version": "2.0",
    "distribution": {
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "de-DE",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "Das BSI ist als Anbieter f\u00fcr die eigenen, zur Nutzung bereitgestellten Inhalte nach den allgemeinen Gesetzen verantwortlich. Nutzerinnen und Nutzer sind jedoch daf\u00fcr verantwortlich, die Verwendung und/oder die Umsetzung der mit den Inhalten bereitgestellten Informationen sorgf\u00e4ltig im Einzelfall zu pr\u00fcfen."
      },
      {
        "category": "description",
        "text": "Exchange ist ein Groupware und Nachrichtensystem der Firma Microsoft.",
        "title": "Produktbeschreibung"
      },
      {
        "category": "summary",
        "text": "Ein entfernter, authentisierter Angreifer kann eine Schwachstelle in Microsoft Exchange Server ausnutzen, um seine Privilegien zu erh\u00f6hen, wodurch er Zugriff auf die Postf\u00e4cher anderer Benutzer innerhalb derselben Organisation erh\u00e4lt und E-Mail-Nachrichten sowie Anh\u00e4nge lesen kann.",
        "title": "Angriff"
      },
      {
        "category": "general",
        "text": "- Windows",
        "title": "Betroffene Betriebssysteme"
      }
    ],
    "publisher": {
      "category": "other",
      "contact_details": "csaf-provider@cert-bund.de",
      "name": "Bundesamt f\u00fcr Sicherheit in der Informationstechnik",
      "namespace": "https://www.bsi.bund.de"
    },
    "references": [
      {
        "category": "self",
        "summary": "WID-SEC-W-2026-3718 - CSAF Version",
        "url": "https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-3718.json"
      },
      {
        "category": "self",
        "summary": "WID-SEC-2026-3718 - Portal Version",
        "url": "https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-3718"
      },
      {
        "category": "external",
        "summary": "Microsoft CVE-2026-96940 vom 2026-10-04",
        "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-96940"
      }
    ],
    "source_lang": "en-US",
    "title": "Microsoft Exchange Server: Schwachstelle erm\u00f6glicht Privilegieneskalation",
    "tracking": {
      "current_release_date": "2026-10-04T22:00:00.000+00:00",
      "generator": {
        "date": "2026-10-05T08:55:51.485+00:00",
        "engine": {
          "name": "BSI-WID",
          "version": "1.6.0"
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      "id": "WID-SEC-W-2026-3718",
      "initial_release_date": "2026-10-04T22:00:00.000+00:00",
      "revision_history": [
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          "date": "2026-10-04T22:00:00.000+00:00",
          "number": "1",
          "summary": "Initiale Fassung"
        }
      ],
      "status": "final",
      "version": "1"
    }
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  "product_tree": {
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        "branches": [
          {
            "branches": [
              {
                "category": "product_version",
                "name": "Server Subscription Edition RTM",
                "product": {
                  "name": "Microsoft Exchange Server Subscription Edition RTM",
                  "product_id": "T060602",
                  "product_identification_helper": {
                    "cpe": "cpe:/a:microsoft:exchange:server_subscription_edition_rtm"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "Server 2016 Cumulative Update 23",
                "product": {
                  "name": "Microsoft Exchange Server 2016 Cumulative Update 23",
                  "product_id": "T060603",
                  "product_identification_helper": {
                    "cpe": "cpe:/a:microsoft:exchange:server_2016_cumulative_update_23"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "Server 2019 Cumulative Update 15",
                "product": {
                  "name": "Microsoft Exchange Server 2019 Cumulative Update 15",
                  "product_id": "T060604",
                  "product_identification_helper": {
                    "cpe": "cpe:/a:microsoft:exchange:server_2019_cumulative_update_15"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "Server 2019 Cumulative Update 14",
                "product": {
                  "name": "Microsoft Exchange Server 2019 Cumulative Update 14",
                  "product_id": "T060605",
                  "product_identification_helper": {
                    "cpe": "cpe:/a:microsoft:exchange:server_2019_cumulative_update_14"
                  }
                }
              }
            ],
            "category": "product_name",
            "name": "Exchange"
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-96940",
      "product_status": {
        "known_affected": [
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          "T060602",
          "T060605",
          "T060604"
        ]
      },
      "release_date": "2026-10-04T22:00:00.000+00:00",
      "title": "CVE-2026-96940"
    }
  ]
}

CVE-2026-96940 (GCVE-0-2026-96940)

Vulnerability from cvelistv5 – Published: 2026-10-02 19:06 – Updated: 2026-10-03 03:55

Title

Microsoft Exchange Server Elevation of Privilege Vulnerability

Summary

Weak authorization in Microsoft Exchange Server allows an authenticated attacker to elevate privileges over a network.

Severity

8.8 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-02 00:00 UTC

CWE

CWE-1390 - Weak Authentication

Assigner

microsoft mitre root Scorecard

References

1 reference

URL	Tags
https://msrc.microsoft.com/update-guide/vulnerabi…	vendor-advisorypatch

Impacted products

4 products

Vendor	Product	Version
Microsoft	Microsoft Exchange Server 2016 Cumulative Update 23	Affected: 15.01.0.0 , < 15.01.2507.075 (custom)
Microsoft	Microsoft Exchange Server 2019 Cumulative Update 14	Affected: 15.02.0.0 , < 15.02.1544.048 (custom)
Microsoft	Microsoft Exchange Server 2019 Cumulative Update 15	Affected: 15.02.0.0 , < 15.02.1748.053 (custom)
Microsoft	Microsoft Exchange Server Subscription Edition RTM	Affected: 15.02.0.0 , < 15.02.2562.053 (custom)

Date Public

2026-10-02 14:00

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
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                "id": "CVE-2026-96940",
                "options": [
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                    "Exploitation": "none"
                  },
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                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-10-02T00:00:00+00:00",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
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          "platforms": [
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          ],
          "product": "Microsoft Exchange Server 2016 Cumulative Update 23",
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      "metrics": [
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            "baseSeverity": "HIGH",
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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WID-SEC-W-2026-3718

CVE-2026-96940 (GCVE-0-2026-96940)

Tags

Sightings

Nomenclature

Related by attack behaviour