CVE-2026-21513
KEVMicrosoft MSHTML Framework Protection Mechanism Failure Vulnerability
8.8
HighPublished:
Last updated:
Source:secure@microsoft.com
Analyzed
Weakness (CWE)
CVSS Vector
v3.1- Attack Vector
- Network
- Attack Complexity
- Low
- Privileges Required
- None
- User Interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Description
Protection mechanism failure in MSHTML Framework allows an unauthorized attacker to bypass a security feature over a network.
References
secure@microsoft.com
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21513af854a3a-2127-422b-91ae-364da2661108
https://www.vicarius.io/vsociety/posts/cve-2026-21513-detection-script-security-feature-bypass-vulnerability-in-mshtml-frameworkaf854a3a-2127-422b-91ae-364da2661108
https://www.vicarius.io/vsociety/posts/cve-2026-21513-mitigation-script-security-feature-bypass-vulnerability-in-mshtml-framework134c704f-9b21-4f2e-91b3-4a467353bcc0
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-21513