CVE-2021-40449

Microsoft Windows — Microsoft Windows Win32k Privilege Escalation Vulnerability
⚠️ CVSS 3.1  7.8 / 10 — HIGH 🔴 CISA Known Exploited Vulnerability

Overview

Unspecified vulnerability allows for an authenticated user to escalate privileges.

https://nvd.nist.gov/vuln/detail/CVE-2021-40449

Key Details

PropertyValue
CVE ID CVE-2021-40449
Vendor / Product Microsoft — Windows
NVD Published2021-10-13
NVD Last Modified2025-10-30
CVSS 3.1 Score7.8
CVSS 3.1 VectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SeverityHIGH
CWE CWE-416
CISA KEV Added2021-11-17
CISA KEV Deadline2021-12-01
Known Ransomware Use ⚠️ Yes

CVSS 3.1 Breakdown

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

Required Action

CISA BOD 22-01 Deadline: 2021-12-01. Apply updates per vendor instructions.

Timeline

DateEvent
2021-11-17Added to CISA Known Exploited Vulnerabilities catalog
2021-12-01CISA BOD 22-01 remediation deadline

References

ResourceType
NVD — CVE-2021-40449 Vulnerability Database
CISA KEV Catalog Entry US Government