CVE-2026-21509
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
Summary
Reliance on untrusted inputs in a security decision in Microsoft Office allows an unauthorized attacker to bypass a security feature locally.
Affected Software
| Vendor | Product | Version Range | Status |
|---|---|---|---|
| Microsoft | Microsoft 365 Apps for Enterprise | 16.0.1 < https://aka.ms/OfficeSecurityReleases | affected |
| Microsoft | Microsoft Office 2016 | 16.0.0 < 16.0.5539.1001 | affected |
| Microsoft | Microsoft Office 2019 | 19.0.0 < 16.0.10417.20095 | affected |
| Microsoft | Microsoft Office LTSC 2021 | 16.0.1 < https://aka.ms/OfficeSecurityReleases | affected |
| Microsoft | Microsoft Office LTSC 2024 | 16.0.0 < https://aka.ms/OfficeSecurityReleases | affected |
Weaknesses
- CWE-807: CWE-807: Reliance on Untrusted Inputs in a Security Decision
ADP Enrichment
CISA ADP Vulnrichment
- SSVC:
- Exploitation: active
- Automatable: no
- Technical Impact: total
Additional References
CVE Program Container
Additional References
- 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
References
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