Improper input validation in Microsoft Windows 10 Version 21h2
CVE-2026-27906
Improper input validation in Windows Hello allows an authorized attacker to bypass a security feature locally.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
EPSS: 0.001 (25.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C.
Affected products
- Microsoft Windows 10 Version 21h2 — versions 10.0.19044.0
- Microsoft Windows 10 Version 22h2 — versions 10.0.19045.0
- Microsoft Windows 11 Version 22h3 — versions 10.0.22631.0
- Microsoft Windows 11 Version 23h2 — versions 10.0.22631.0
- Microsoft Windows 11 Version 24h2 — versions 10.0.26100.0
- Microsoft Windows 11 Version 25h2 — versions 10.0.26200.0
- Microsoft Windows 11 Version 26h1 — versions 10.0.28000.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- Windows Hello Security Feature Bypass Vulnerability (vendor-advisory, patch)
Frequently asked questions
- What is CVE-2026-27906?
- CVE-2026-27906 is a medium-severity vulnerability in Microsoft Windows 10 Version 21h2, classified under Improper Input Validation. CVSS score: 4.4/10. Published 2026-04-14.
- How severe is CVE-2026-27906?
- Medium severity. CVSS v3 base score is 4.4 out of 10.
- Is CVE-2026-27906 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.