CVE-2026-21509
Published Jan 26, 2026
Last updated 2 days ago
- Description
- Reliance on untrusted inputs in a security decision in Microsoft Office allows an unauthorized attacker to bypass a security feature locally.
- Source
- secure@microsoft.com
- NVD status
- Analyzed
- Products
- 365_apps, office, office_long_term_servicing_channel
CVSS 3.1
- Type
- Secondary
- Base score
- 7.8
- Impact score
- 5.9
- Exploitability score
- 1.8
- Vector string
- CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Severity
- HIGH
Data from CISA
- Vulnerability name
- Microsoft Office Security Feature Bypass Vulnerability
- Exploit added on
- Jan 26, 2026
- Exploit action due
- Feb 16, 2026
- Required action
- Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- secure@microsoft.com
- CWE-807
- Hype score
- Not currently trending
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