MSHTML CVE-2021-40444 Attacks
ActiveX-loaded malicious documents used as initial access
MSHTML CVE-2021-40444 Attacks — ActiveX-loaded malicious documents used as initial access Relates to CVE-2021-40444. (Source: CISA advisory AA21-257A)
Definition
ActiveX-loaded malicious documents used as initial access
Why It Matters / Impact
ActiveX-loaded malicious documents used as initial access
Current Status
- Review status: published
- Last updated: 2026-08-26
- Evidence: 2 source(s) · 1 CVE(s) linked
- Confidence: 85%
Timeline
- 2021-09 — In-the-wild exploitation
- 2021-10 — Patch released after active abuse
Sources
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