SARA / Free Tools / CVE / CVE-2021-40444

CVE-2021-40444 — <p>Microsoft is investigating reports of a remote code execution vulnerability i

<p>Microsoft is investigating reports of a remote code execution vulnerability in MSHTML that affects Microsoft Windows. Microsoft is aware of targeted attacks that attempt to exploit this vulnerability by using specially-crafted Microsoft Office documents.</p> <p&

CVSS
8.8
EPSS
(top 0.00%)
CWE
CWE-22
Published
2021-09-15 (4y 9m ago)
Last modified
2025-10-30
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L
CISA KEV — Actively Exploited
Added to KEV
BOD 22-01 due
Ransomware use
Known

01What is this vulnerability?

<p>Microsoft is investigating reports of a remote code execution vulnerability in MSHTML that affects Microsoft Windows. Microsoft is aware of targeted attacks that attempt to exploit this vulnerability by using specially-crafted Microsoft Office documents.</p> <p>An attacker could craft a malicious ActiveX control to be used by a Microsoft Office document that hosts the browser rendering engine…

02Affected products

No structured affected-product list available — see references below for vendor advisories.

03Active exploitation status

Yes — actively exploited. Added to the CISA KEV catalog on —. Ransomware use: Known.

04Recommended remediation

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

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07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

09References

No additional references available in the KB record.

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