CVE-2020-1054VulnerabilityPublished 11/03/2021Updated 10/24/2026

CVE-2020-1054: Microsoft Win32k Privilege Escalation Vulnerability

Affects Microsoft Win32kSource CISA KEV

Severity

High

No CVSS score published yet

Exploitation: Actively exploited – in CISA KEV since 11/03/2021
KEV deadline: 05/03/2022
EPSS: 53.9% chance of exploitation in 30 days – higher than 99% of CVEs

What to do

CISA required action

Apply updates per vendor instructions.

nvd.nist.gov/vuln/detail/CVE-2020-1054 (opens in a new tab)

Description

CVE-2020-1054 is a privilege escalation vulnerability in the Microsoft Win32k kernel-mode driver. The flaw arises from improper handling of objects in memory, allowing attackers to execute code with kernel-level privileges. This vulnerability has been exploited in the wild, indicating active threat usage. It affects the Windows operating system component Win32k. No specific affected versions are provided. The severity is high due to the potential for attackers to gain elevated privileges.

Summary

Microsoft Win32k contains a privilege escalation vulnerability (CVE-2020-1054) caused by improper handling of objects in memory within the Windows kernel-mode driver. Successful exploitation enables attackers to execute arbitrary code in kernel mode, potentially leading to full system compromise. This vulnerability has been observed in active exploitation scenarios. No explicit affected versions or patch information is provided in the source data.

Impact

Exploitation of this vulnerability allows attackers to execute code in kernel mode, resulting in privilege escalation. This can lead to complete control over the affected system, bypassing security restrictions and potentially enabling further malicious activities. The vulnerability has been exploited in the wild, confirming its practical impact.

Mitigation

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no patch or official fix information is provided, users should monitor Microsoft advisories for updates and apply any released security updates promptly.

Weaknesses

CWE-787Out-of-bounds Write (opens in a new tab)

What to do

Description

AnalysisAI-generated, updated 10/24/2026, 09:10:57 UTC

Weaknesses

References

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