Description
Protection mechanism failure in MSHTML Framework allows an unauthorized attacker to bypass a security feature over a network.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Microsoft Windows 10 Version 1607
10.0.14393.0 to < 10.0.14393.8868affected
Microsoft Windows 10 Version 1809
10.0.17763.0 to < 10.0.17763.8389affected
Microsoft Windows 10 Version 21H2
10.0.19044.0 to < 10.0.19044.6937affected
Microsoft Windows 10 Version 22H2
10.0.19045.0 to < 10.0.19045.6937affected
Microsoft Windows 11 version 22H3
10.0.22631.0 to < 10.0.22631.6649affected
Microsoft Windows 11 Version 23H2
10.0.22631.0 to < 10.0.22631.6649affected
Microsoft Windows 11 Version 24H2
10.0.26100.0 to < 10.0.26100.7840affected
Microsoft Windows 11 Version 25H2
10.0.26200.0 to < 10.0.26200.7840affected
Microsoft Windows 11 version 26H1
10.0.28000.0 to < 10.0.28000.1575affected
Microsoft Windows 11 Version 26H1
10.0.28000.0 to < 10.0.28000.1575affected
Microsoft Windows Server 2012
6.2.9200.0 to < 6.2.9200.25923affected
Microsoft Windows Server 2012 (Server Core installation)
6.2.9200.0 to < 6.2.9200.25923affected
Microsoft Windows Server 2012 R2
6.3.9600.0 to < 6.3.9600.23022affected
Microsoft Windows Server 2012 R2 (Server Core installation)
6.3.9600.0 to < 6.3.9600.23022affected
Microsoft Windows Server 2016
10.0.14393.0 to < 10.0.14393.8868affected
Microsoft Windows Server 2016 (Server Core installation)
10.0.14393.0 to < 10.0.14393.8868affected
Microsoft Windows Server 2019
10.0.17763.0 to < 10.0.17763.8389affected
Microsoft Windows Server 2019 (Server Core installation)
10.0.17763.0 to < 10.0.17763.8389affected
Microsoft Windows Server 2022
10.0.20348.0 to < 10.0.20348.4773affected
Microsoft Windows Server 2022, 23H2 Edition (Server Core installation)
10.0.25398.0 to < 10.0.25398.2149affected
Microsoft Windows Server 2025
10.0.26100.0 to < 10.0.26100.32370affected
Microsoft Windows Server 2025 (Server Core installation)
10.0.26100.0 to < 10.0.26100.32370affected
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21513 ↗
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-21513 ↗
- https://www.vicarius.io/vsociety/posts/cve-2026-21513-detection-script-security-feature-bypass-vulnerability-in-mshtml-framework ↗
- https://www.vicarius.io/vsociety/posts/cve-2026-21513-mitigation-script-security-feature-bypass-vulnerability-in-mshtml-framework ↗