CVE-2026-21510: Windows Shell Security Feature Bypass Vulnerability

Overview

Severity

High (CVSS 8.8)

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C

Category

Security Feature Bypass

Exploit Status

Actively Exploited

Exploitation Likelihood

Detected

Publicly Disclosed

Yes

Patch Tuesday

2026-Feb

Released

2026-02-10

EPSS Score

3.52% (percentile: 87.7%)

CISA KEV

Listed — due 2026-03-03

Description

Protection mechanism failure in Windows Shell allows an unauthorized attacker to bypass a security feature over a network.

FAQ

According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do? To successfully exploit this vulnerability, an attacker must convince a user to open a malicious link or shortcut file. What kind of security feature could be bypassed by successfully exploiting this vulnerability? An attacker could bypass Windows SmartScreen and Windows Shell security prompts by exploiting improper handling in Windows Shell components, allowing attacker‑controlled content to execute without user warning or consent.

Detection & Weaponization (1 sources)

Maturity: Exploit

• GitHub PoC: 1 repositories

Affected Products (31)

Windows

• Windows 10 Version 1809 for 32-bit Systems
• Windows 10 Version 1809 for x64-based Systems
• Windows Server 2019
• Windows Server 2019 (Server Core installation)
• Windows Server 2022
• Windows Server 2022 (Server Core installation)
• Windows 10 Version 21H2 for 32-bit Systems
• Windows 10 Version 21H2 for ARM64-based Systems
• Windows 10 Version 21H2 for x64-based Systems
• Windows Server 2025 (Server Core installation)
• Windows 11 Version 25H2 for ARM64-based Systems
• Windows 11 Version 25H2 for x64-based Systems
• Windows 11 Version 23H2 for ARM64-based Systems
• Windows 11 Version 23H2 for x64-based Systems
• Windows Server 2022, 23H2 Edition (Server Core installation)
• Windows 11 Version 24H2 for ARM64-based Systems
• Windows 11 Version 24H2 for x64-based Systems
• Windows Server 2025
• Windows 10 Version 1607 for 32-bit Systems
• Windows 10 Version 1607 for x64-based Systems
• Windows Server 2016
• Windows Server 2016 (Server Core installation)
• Windows 11 Version 26H1 for ARM64-based Systems
• Windows 11 version 26H1 for x64-based Systems

ESU

• Windows 10 Version 22H2 for x64-based Systems
• Windows 10 Version 22H2 for ARM64-based Systems
• Windows 10 Version 22H2 for 32-bit Systems
• Windows Server 2012
• Windows Server 2012 (Server Core installation)
• Windows Server 2012 R2
• Windows Server 2012 R2 (Server Core installation)

Security Updates (14)

• 5075904
• 5075906
• 5075943
• 5075912
• 5075899
• 5075942
• 5077181
• 5077212
• 5075941
• 5075897
• 5075999
• 5075971
• 5075970
• 5077179

Acknowledgments

Anonymous, Google Threat Intelligence Group, Microsoft Threat Intelligence Center (MSTIC), Microsoft Security Response Center (MSRC), and Office Product Group Security Team

Revision History

• 2026-02-10: Information published.