HIGHCVSS 7.8Actively exploited · CISA KEV since 2026-01-26Vulnerability
CVE-2026-21509
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.
Properties
- Euvd product
- Microsoft Office 2019, Microsoft Office LTSC 2021, Microsoft Office LTSC 2024, Microsoft 365 Apps for Enterprise, Microsoft Office 2016
- Vulnerability name
- Microsoft Office Security Feature Bypass Vulnerability
- First seen
- 2026-07-30T20:47:35+00:00
- Cvss score
- 7.8
- Epss score
- 0.70795
- Last seen
- 2026-10-19T12:00:27+00:00
- Due date
- 2026-02-16
- Euvd assigner
- microsoft
- Retrieved at
- 2026-10-21T01:24:49+00:00
- Exploited euvd since
- 2026-01-26T00:00:00+00:00
- Src batch id
- epss_history-20261020T103617Z-728ddd
- Source url
- https://epss.empiricalsecurity.com/epss_scores-2026-10-19.csv.gz
- Date added
- 2026-01-26
- Score
- 7.8
- Euvd base score version
- 3.1
- Fetched at
- 2026-10-20T10:36:20+00:00
- Euvd vendor
- Microsoft
- Cvss vector
- CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- In Signal since
- initial import (Sep 2026)
- Euvd base score
- 7.8
Related Entities (45 · showing 43)
HAS_INDICATOR (22 · showing 20)
AFFECTS_PRODUCT (10)
MENTIONED_IN (9)
INVOLVES (2)
DESCRIBES (1)
HAS_WEAKNESS (1)
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