CVE-2020-1054
Published: November 3, 2021
Official Description
Microsoft Win32k contains a privilege escalation vulnerability when the Windows kernel-mode driver fails to properly handle objects in memory. Successful exploitation allows an attacker to execute code in kernel mode.
CISA KEV Advisory
Microsoft Win32k Privilege Escalation Vulnerability
Microsoft Win32k contains a privilege escalation vulnerability when the Windows kernel-mode driver fails to properly handle objects in memory. Successful exploitation allows an attacker to execute code in kernel mode.
Apply updates per vendor instructions.
Risk Analysis
A privilege escalation vulnerability exists in Microsoft Win32k due to improper handling of objects in memory by the Windows kernel-mode driver. With an EPSS score of 0.80933 and confirmed exploitation, this flaw allows an attacker to execute code in kernel mode, gaining full system control.
This vulnerability is actively exploited in the wild and is listed in CISA's KEV catalog, confirming its use by attackers. The ability to execute code in kernel mode makes it a critical privilege escalation threat.
Apply the latest security updates from Microsoft to patch the Win32k component. Regularly update and patch Windows systems to prevent privilege escalation attacks.
Technical Analysis
CVE-2020-1054 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-2020-1054 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-2020-1054 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