CVE-2026-27906: CWE-20: Improper Input Validation in Microsoft Windows 10 Version 21H2
Improper input validation in Windows Hello allows an authorized attacker to bypass a security feature locally.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-27906) is caused by improper input validation within the Windows Hello component of Windows 10 Version 21H2 (build 10.0.19044.0). It enables an attacker with authorized local access and high privileges to bypass a security feature, potentially compromising confidentiality. The CVSS 3.1 base score is 4.4, reflecting a medium severity with local attack vector, low attack complexity, and no user interaction required. Microsoft has released an official fix to address this issue.
Potential Impact
An authorized attacker with local access and high privileges can exploit this vulnerability to bypass a security feature in Windows Hello, potentially leading to unauthorized access to sensitive information (confidentiality impact). There is no impact on integrity or availability. No known exploits are reported in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-27906 to remediate this vulnerability.
CVE-2026-27906: CWE-20: Improper Input Validation in Microsoft Windows 10 Version 21H2
Description
Improper input validation in Windows Hello allows an authorized attacker to bypass a security feature locally.
CVSS v3.1
Score 4.4medium
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-27906) is caused by improper input validation within the Windows Hello component of Windows 10 Version 21H2 (build 10.0.19044.0). It enables an attacker with authorized local access and high privileges to bypass a security feature, potentially compromising confidentiality. The CVSS 3.1 base score is 4.4, reflecting a medium severity with local attack vector, low attack complexity, and no user interaction required. Microsoft has released an official fix to address this issue.
Potential Impact
An authorized attacker with local access and high privileges can exploit this vulnerability to bypass a security feature in Windows Hello, potentially leading to unauthorized access to sensitive information (confidentiality impact). There is no impact on integrity or availability. No known exploits are reported in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-27906 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-02-24T21:35:49.685Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-27906","vendor":"Microsoft"}]
Threat ID: 69de7a1d82d89c981fd6a72b
Added to database: 4/14/2026, 5:32:13 PM
Last enriched: 5/19/2026, 10:37:00 AM
Last updated: 5/30/2026, 2:21:13 AM
Views: 49
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