CVE Watch—

CVE-2026-21510

Microsoft Windows Shell Protection Mechanism Failure Vulnerability

CVSS

—

No CVSS

EPSS

25.8%

p98

KEV

YES

Feb 10, 2026

Exploit Today

0-100

Published: — · Last modified: —

EPSS · 30d

25.8%EPSS · 30 days25.8%

2026-06-302026-07-16

KEV catalog record

Product

Microsoft / Windows

Vulnerability

Microsoft Windows Shell Protection Mechanism Failure Vulnerability

Added to KEV

Feb 10, 2026

Remediate by

Mar 3, 2026

Known ransomware use

Summary description

Microsoft Windows Shell contains a protection mechanism failure vulnerability that could allow an unauthorized attacker to bypass a security feature over a network.

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.

Notes

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21510 ; https://nvd.nist.gov/vuln/detail/CVE-2026-21510

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