CVE-2026-21509
Microsoft Office Security Feature Bypass Vulnerability
En bref
- Source
- NVD
- EPSS
- EPSS 70.80 % · centile 99 ()
- État
- PUBLISHED
- Publiée
- Mise à jour
- Attribuée par
- microsoft
- Statut NVD
- Analyzed
Description
Reliance on untrusted inputs in a security decision in Microsoft Office allows an unauthorized attacker to bypass a security feature locally.
Faiblesses (CWE)
- CWE-807 — Reliance on Untrusted Inputs in a Security Decision
Références
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21509
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-21509
- https://www.vicarius.io/vsociety/posts/cve-2026-21509-detection-script-microsoft-office-security-feature-bypass-vulnerability
- https://www.vicarius.io/vsociety/posts/cve-2026-21509-mitigation-script-microsoft-office-security-feature-bypass-vulnerability
Scores
| Version | Score | Vecteur | Évalué par |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.8 | 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 | microsoft |
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H | NVD · secure@microsoft.com (Secondary) |
Références européennes
- ENISA EUVD · EUVD-2026-4666
- GCVE · GCVE-0-2026-21509
Avis du CERT-FR
- CERTFR-2026-AVI-0089 — Vulnérabilité dans Microsoft Office · cert.ssi.gouv.fr
Configurations affectées (CPE NVD)
cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:*cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:*cpe:2.3:a:microsoft:office:2016:*:*:*:*:*:x64:*cpe:2.3:a:microsoft:office:2016:*:*:*:*:*:x86:*cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:x64:*cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:x86:*cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x64:*cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x86:*cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x64:*cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x86:*
Produits affectés
| Produit | Versions |
|---|---|
| Microsoft · Microsoft 365 Apps for Enterprise | affected 16.0.1 < https://aka.ms/OfficeSecurityReleases |
| Microsoft · Microsoft Office 2016 | affected 16.0.0 < 16.0.5539.1001 |
| Microsoft · Microsoft Office 2019 | affected 19.0.0 < 16.0.10417.20095 |
| Microsoft · Microsoft Office LTSC 2021 | affected 16.0.1 < https://aka.ms/OfficeSecurityReleases |
| Microsoft · Microsoft Office LTSC 2024 | affected 16.0.0 < https://aka.ms/OfficeSecurityReleases |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| CISA Known Exploited Vulnerabilities | CC0 1.0 |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |