CVE-2026-21513
Protection mechanism failure in MSHTML Framework allows an unauthorized attacker to bypass a security feature over a network.
ACTIVELY EXPLOITED IN THE WILD
This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
Microsoft MSHTML Framework Protection Mechanism Failure Vulnerability
Microsoft Windows
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
2/10/2026
https://msrc.microsoft.com/update-guide/advisory/CVE-2026-21513 ; https://nvd.nist.gov/vuln/detail/CVE-2026-21513
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score (Exploitation Probability)
This vulnerability has a 24.96% probability of being exploited in the next 30 days, ranking higher than 96% of all scored CVEs.
CWE Classification
Related Vulnerabilities
Same Weakness Type(CWE-693)
Protection mechanism failure in Windows Shell allows an unauthorized attacker to perform spoofing over a network.
Protection mechanism failure in Windows Shell allows an unauthorized attacker to bypass a security feature over a network.
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Similar SeverityHIGH
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