CVE-2021-41357
Published: April 25, 2022
Official Description
Microsoft Win32k contains an unspecified vulnerability that allows for privilege escalation.
CISA KEV Advisory
Microsoft Win32k Privilege Escalation Vulnerability
Microsoft Win32k contains an unspecified vulnerability that allows for privilege escalation.
Apply updates per vendor instructions.
Risk Analysis
This unspecified vulnerability in Microsoft Win32k allows for privilege escalation, enabling an attacker to gain higher system privileges. Its inclusion in CISA's KEV catalog and an EPSS score of 0.07369 confirm active exploitation and a high likelihood of future attacks.
This vulnerability is actively exploited in the wild, as confirmed by its presence in CISA's KEV catalog. Exploitation typically requires local access to the affected system.
Install the latest security updates from Microsoft to patch the Win32k component. Implement the principle of least privilege to minimize the impact of successful privilege escalation attempts.
Technical Analysis
CVE-2021-41357 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
CISA has added CVE-2021-41357 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
Affected Vendors & Products
Exploit & PoC Resources
All References (1)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-41357 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1