CVE-2026-21513

high Microsoft ⚠️ CISA KEV — Exploited in the Wild
CVSS v3 Base Score
8.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
EPSS Score
5.2%
Exploitation probability in 30 days
Top 10% most likely to be exploited
Attack Characteristics
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Published: February 10, 2026 (93 days ago)
Last Modified: March 13, 2026
Vendor: Microsoft
Source: MITRE

⚠️ CISA Known Exploited Vulnerability

Added to KEV: 2026-02-10
Remediation Due: 2026-03-03 (⚠ 73d overdue)

Description

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

CWE

CWE-693

Affected Products

Microsoft Windows 10 Version 1607Microsoft Windows 10 Version 1809Microsoft Windows 10 Version 21H2Microsoft Windows 10 Version 22H2Microsoft Windows 11 version 22H3Microsoft Windows 11 Version 23H2Microsoft Windows 11 Version 24H2Microsoft Windows 11 Version 25H2Microsoft Windows 11 version 26H1Microsoft Windows 11 Version 26H1

References

🔗 msrc.microsoft.com