Microsoft Windows Shell Protection Mechanism Failure Vulnerability

Technical Severity

CVSS v3.1 Metrics

HIGH

8.8 / 10

Minimal Risk Critical

Vector Specification

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Exploitation Likelihood

EPSS Prediction

2.72 %

Predictive Probability

Percentile Rank

85.7 th

Documented as more likely to be exploited than 85.7% of known CVEs.

Detection Date

Feb 10, 2026

Remediation Due

Mar 03, 2026

CISA Catalog Active

Threat Analysis

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

Remediation Directive

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

External Intelligence

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21510

NVD

National Vulnerability Database

https://nvd.nist.gov/vuln/detail/CVE-2026-21510