MSHTML Framework Security Feature Bypass Vulnerability
CVSS v3
8.8
HIGH
EPSS Score
28.1%
exploit probability
CISA KEV
Yes
known exploited
Exploitation
active
SSVC status
Protection mechanism failure in MSHTML Framework allows an unauthorized attacker to bypass a security feature over a network.
Protection mechanism failure in MSHTML Framework allows an unauthorized attacker to bypass a security feature over a network.
Yes. CVE-2026-21513 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 3/3/2026.
CVE-2026-21513 has a CVSS v3 base score of 8.8 (HIGH severity), with vector string 3.1.
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Ranked by exploit probability (EPSS).