CVE-2021-33742

Microsoft Windows — Microsoft Windows MSHTML Platform Remote Code Execution Vulnerability
⚠️ CVSS 3.1  7.5 / 10 — HIGH 🔴 CISA Known Exploited Vulnerability

Overview

Microsoft Windows MSHTML Platform contains an unspecified vulnerability that allows for remote code execution.

https://nvd.nist.gov/vuln/detail/CVE-2021-33742

Key Details

PropertyValue
CVE ID CVE-2021-33742
Vendor / Product Microsoft — Windows
NVD Published2021-06-08
NVD Last Modified2025-10-29
CVSS 3.1 Score7.5
CVSS 3.1 VectorCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
SeverityHIGH
CWE CWE-787
CISA KEV Added2021-11-03
CISA KEV Deadline2021-11-17
Known Ransomware Use No

CVSS 3.1 Breakdown

Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Required Action

CISA BOD 22-01 Deadline: 2021-11-17. Apply updates per vendor instructions.

Timeline

DateEvent
2021-11-03Added to CISA Known Exploited Vulnerabilities catalog
2021-11-17CISA BOD 22-01 remediation deadline

References

ResourceType
NVD — CVE-2021-33742 Vulnerability Database
CISA KEV Catalog Entry US Government