CVE record
CVE-2026-21513
Microsoft MSHTML Framework Protection Mechanism Failure Vulnerability
Microsoft MSHTML Framework contains a protection mechanism failure vulnerability that could allow an unauthorized attacker to bypass a security feature over a network.
CVE evidence
Known exploitation
Listed in CISA KEV
Absence from the fetched catalog does not establish that exploitation has not occurred.
Severity
unknown
No parseable CVSS vector returned
Affected packages
0
Supported package records returned by OSV. Vendor and product names are not used to infer matches.
CISA Known Exploited Vulnerabilities
Catalog record
- Vendor / project
- Microsoft
- Product
- Windows
- Date added
- Feb 10, 2026
- CISA federal remediation due date
- Mar 3, 2026
- Required action
- Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- Known ransomware campaign use
- Unknown
- CWE
- CWE-693
OSV package mapping
Affected open-source packages
OSV did not return a package mapping in the five supported ecosystems. RequestGuard does not infer package names from the CISA vendor or product fields.