Description
Protection mechanism failure in MSHTML Framework allows an unauthorized attacker to bypass a security feature over a network.
Metrics
CVSS 3.1 8.8/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows 10 Version 1607 | >= 10.0.14393.0, < 10.0.14393.8868 |
| Microsoft | Windows 10 Version 1809 | >= 10.0.17763.0, < 10.0.17763.8389 |
| Microsoft | Windows 10 Version 21H2 | >= 10.0.19044.0, < 10.0.19044.6937 |
| Microsoft | Windows 10 Version 22H2 | >= 10.0.19045.0, < 10.0.19045.6937 |
| Microsoft | Windows 11 version 22H3 | >= 10.0.22631.0, < 10.0.22631.6649 |
| Microsoft | Windows 11 Version 23H2 | >= 10.0.22631.0, < 10.0.22631.6649 |
| Microsoft | Windows 11 Version 24H2 | >= 10.0.26100.0, < 10.0.26100.7840 |
| Microsoft | Windows 11 Version 25H2 | >= 10.0.26200.0, < 10.0.26200.7840 |
| Microsoft | Windows 11 version 26H1 | >= 10.0.28000.0, < 10.0.28000.1575 |
| Microsoft | Windows 11 Version 26H1 | >= 10.0.28000.0, < 10.0.28000.1575 |
| Microsoft | Windows Server 2012 | >= 6.2.9200.0, < 6.2.9200.25923 |
| Microsoft | Windows Server 2012 (Server Core installation) | >= 6.2.9200.0, < 6.2.9200.25923 |
| Microsoft | Windows Server 2012 R2 | >= 6.3.9600.0, < 6.3.9600.23022 |
| Microsoft | Windows Server 2012 R2 (Server Core installation) | >= 6.3.9600.0, < 6.3.9600.23022 |
| Microsoft | Windows Server 2016 | >= 10.0.14393.0, < 10.0.14393.8868 |
| Microsoft | Windows Server 2016 (Server Core installation) | >= 10.0.14393.0, < 10.0.14393.8868 |
| Microsoft | Windows Server 2019 | >= 10.0.17763.0, < 10.0.17763.8389 |
| Microsoft | Windows Server 2019 (Server Core installation) | >= 10.0.17763.0, < 10.0.17763.8389 |
| Microsoft | Windows Server 2022 | >= 10.0.20348.0, < 10.0.20348.4773 |
| Microsoft | Windows Server 2022, 23H2 Edition (Server Core installation) | >= 10.0.25398.0, < 10.0.25398.2149 |
| Microsoft | Windows Server 2025 | >= 10.0.26100.0, < 10.0.26100.32370 |
| Microsoft | Windows Server 2025 (Server Core installation) | >= 10.0.26100.0, < 10.0.26100.32370 |
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21513Vendor Advisory
- https://www.vicarius.io/vsociety/posts/cve-2026-21513-detection-script-security-feature-bypass-vulnerability-in-mshtml-frameworkThird Party Advisory
- https://www.vicarius.io/vsociety/posts/cve-2026-21513-mitigation-script-security-feature-bypass-vulnerability-in-mshtml-frameworkMitigation, Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-21513US Government Resource
Timeline
- Published
- Feb 10, 2026
- Last modified
- Jun 17, 2026
- Added to CISA KEV
- Feb 10, 2026
- NVD status
- Analyzed