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// vulnerability record
cached · NVD via COSMOS syncCVE-2026-21509
HIGHKEVpublished 2026-01-26 18:16 UTC · 7 months ago · modified 2026-06-25 05:16 UTC
7.8
CVSS / 10
// description
Microsoft Office contains a security feature bypass vulnerability in which reliance on untrusted inputs in a security decision in Microsoft Office could allow an unauthorized attacker to bypass a security feature locally. Some of the impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version.
// required action (CISA KEV)
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
added 2026-01-26 00:00 UTC
// weaknesses (CWE)
- CWE-807
// references (4)
- https://msrc.microsoft.com/update-guide/vulnerability/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
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-21509