Vulnerability-Lookup

WID-SEC-W-2026-0221

Vulnerability from csaf_certbund - Published: 2026-01-26 23:00 - Updated: 2026-01-26 23:00

Summary

Microsoft Office-Produkte und Microsoft 365-Apps: Schwachstelle ermöglicht Umgehen von Sicherheitsvorkehrungen

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: Die Microsoft Office Suite beinhaltet zahlreiche Büroanwendungen wie Textverarbeitung, Tabellenkalkulation, Datenbank und weitere Applikationen. Microsoft Office LTSC 2021 ist eine Office-Suite für Unternehmen, die als Volumenlizenz mit langfristigem Support angeboten wird. Microsoft 365 Apps ist eine Office Suite für zahlreiche Büroanwendungen. Microsoft Office LTSC 2024 ist eine Office-Suite für Unternehmen, die als Volumenlizenz ohne Cloud-Anbindung angeboten wird.

Angriff: Ein lokaler Angreifer kann eine Schwachstelle in Microsoft Office 2016, Office 2019, Office LTSC 2021, Office LTSC 2024 und Microsoft 365 Apps for Enterprise ausnutzen, um Sicherheitsvorkehrungen zu umgehen.

Betroffene Betriebssysteme: - Windows

CVE-2026-21509

Affected products

Known affected 5 products

Product	Identifier	Version
Microsoft Office 2016 Microsoft / Office	`cpe:/a:microsoft:office:2016`	2016
Microsoft Microsoft Office LTSC 2024 Microsoft	`cpe:/a:microsoft:microsoft_office_ltsc_2024:-`	—
Microsoft Microsoft Office LTSC 2021 Microsoft	`cpe:/a:microsoft:microsoft_office_ltsc_2021:-`	—
Microsoft Office 2019 Microsoft / Office	`cpe:/a:microsoft:office:2019`	2019
Microsoft 365 Apps Microsoft	`cpe:/a:microsoft:365_apps:-`	—

References

4 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
https://github.com/advisories/GHSA-ch84-h92g-mw93	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": "Die Microsoft Office Suite beinhaltet zahlreiche B\u00fcroanwendungen wie Textverarbeitung, Tabellenkalkulation, Datenbank und weitere Applikationen.\r\nMicrosoft Office LTSC 2021 ist eine Office-Suite f\u00fcr Unternehmen, die als Volumenlizenz mit langfristigem Support angeboten wird.\r\nMicrosoft 365 Apps ist eine Office Suite f\u00fcr zahlreiche B\u00fcroanwendungen.\r\nMicrosoft Office LTSC 2024 ist eine Office-Suite f\u00fcr Unternehmen, die als Volumenlizenz ohne Cloud-Anbindung angeboten wird.",
        "title": "Produktbeschreibung"
      },
      {
        "category": "summary",
        "text": "Ein lokaler Angreifer kann eine Schwachstelle in Microsoft Office 2016, Office 2019, Office LTSC 2021, Office LTSC 2024 und Microsoft 365 Apps for Enterprise ausnutzen, um Sicherheitsvorkehrungen zu umgehen.",
        "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-2026-0221 - CSAF Version",
        "url": "https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-0221.json"
      },
      {
        "category": "self",
        "summary": "WID-SEC-2026-0221 - Portal Version",
        "url": "https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-0221"
      },
      {
        "category": "external",
        "summary": "Microsoft Security Update Guide vom 2026-01-26",
        "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21509"
      },
      {
        "category": "external",
        "summary": "GitHub Advisory Database vom 2026-01-26",
        "url": "https://github.com/advisories/GHSA-ch84-h92g-mw93"
      }
    ],
    "source_lang": "en-US",
    "title": "Microsoft Office-Produkte und Microsoft 365-Apps: Schwachstelle erm\u00f6glicht Umgehen von Sicherheitsvorkehrungen",
    "tracking": {
      "current_release_date": "2026-01-26T23:00:00.000+00:00",
      "generator": {
        "date": "2026-01-27T09:36:10.985+00:00",
        "engine": {
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          "version": "1.5.0"
        }
      },
      "id": "WID-SEC-W-2026-0221",
      "initial_release_date": "2026-01-26T23:00:00.000+00:00",
      "revision_history": [
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          "date": "2026-01-26T23:00:00.000+00:00",
          "number": "1",
          "summary": "Initiale Fassung"
        }
      ],
      "status": "final",
      "version": "1"
    }
  },
  "product_tree": {
    "branches": [
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            "name": "Microsoft 365 Apps",
            "product": {
              "name": "Microsoft 365 Apps",
              "product_id": "T050314",
              "product_identification_helper": {
                "cpe": "cpe:/a:microsoft:365_apps:-"
              }
            }
          },
          {
            "category": "product_name",
            "name": "Microsoft Microsoft Office LTSC 2021",
            "product": {
              "name": "Microsoft Microsoft Office LTSC 2021",
              "product_id": "T050315",
              "product_identification_helper": {
                "cpe": "cpe:/a:microsoft:microsoft_office_ltsc_2021:-"
              }
            }
          },
          {
            "category": "product_name",
            "name": "Microsoft Microsoft Office LTSC 2024",
            "product": {
              "name": "Microsoft Microsoft Office LTSC 2024",
              "product_id": "T050316",
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          },
          {
            "branches": [
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                "category": "product_version",
                "name": "2016",
                "product": {
                  "name": "Microsoft Office 2016",
                  "product_id": "T050309",
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                    "cpe": "cpe:/a:microsoft:office:2016"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "2019",
                "product": {
                  "name": "Microsoft Office 2019",
                  "product_id": "T050311",
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                    "cpe": "cpe:/a:microsoft:office:2019"
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          "T050311",
          "T050314"
        ]
      },
      "release_date": "2026-01-26T23:00:00.000+00:00",
      "title": "CVE-2026-21509"
    }
  ]
}

CVE-2026-21509 (GCVE-0-2026-21509)

Vulnerability from cvelistv5 – Published: 2026-01-26 17:06 – Updated: 2026-04-01 13:49

Title

Microsoft Office Security Feature Bypass Vulnerability

Summary

Reliance on untrusted inputs in a security decision in Microsoft Office allows an unauthorized attacker to bypass a security feature locally.

Severity

7.8 (High)


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

SSVC

Exploitation: active Automatable: no Technical Impact: total

CISA Coordinator (v2.0.3)

CWE

CWE-807 - Reliance on Untrusted Inputs in a Security Decision

Assigner

microsoft

References

4 references

URL	Tags
https://msrc.microsoft.com/update-guide/vulnerabi…	vendor-advisorypatch
https://www.cisa.gov/known-exploited-vulnerabilit…	government-resource
https://www.vicarius.io/vsociety/posts/cve-2026-2…
https://www.vicarius.io/vsociety/posts/cve-2026-2…

Impacted products

5 products

Vendor	Product	Version
Microsoft	Microsoft 365 Apps for Enterprise	Affected: 16.0.1 , < https://aka.ms/OfficeSecurityReleases (custom)
Microsoft	Microsoft Office 2016	Affected: 16.0.0 , < 16.0.5539.1001 (custom)
Microsoft	Microsoft Office 2019	Affected: 19.0.0 , < 16.0.10417.20095 (custom)
Microsoft	Microsoft Office LTSC 2021	Affected: 16.0.1 , < https://aka.ms/OfficeSecurityReleases (custom)
Microsoft	Microsoft Office LTSC 2024	Affected: 16.0.0 , < https://aka.ms/OfficeSecurityReleases (custom)

Date Public

2026-01-26 16:00

Show details on NVD website

JSON

To clipboard

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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.

Detection rules are retrieved from Rulezet.

Action not permitted

WID-SEC-W-2026-0221

CVE-2026-21509 (GCVE-0-2026-21509)

Tags

Sightings

Nomenclature