CVE WatchOct 8, 2026

CVE-2020-1054

Microsoft Win32k Privilege Escalation Vulnerability

CVSS

7.0

High

EPSS

54.2%

p99

KEV

YES

Nov 3, 2021

Exploit Today

0-100

Published: May 21, 2020 · Last modified: Oct 8, 2026 · CWE-787

EPSS · 30d

54.2%EPSS · 30 days54.2%

2026-09-172026-10-15

KEV catalog record

Product

Microsoft / Win32k

Vulnerability

Microsoft Win32k Privilege Escalation Vulnerability

Added to KEV

Nov 3, 2021

Remediate by

May 3, 2022

Known ransomware use

Summary 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.

Required action

Apply updates per vendor instructions.

Notes

https://nvd.nist.gov/vuln/detail/CVE-2020-1054

Technical description

An elevation of privilege vulnerability exists in Windows when the Windows kernel-mode driver fails to properly handle objects in memory. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. To exploit this vulnerability, an attacker would first have to log on to the system. An attacker could then run a specially crafted application that could exploit the vulnerability and take control of an affected system. The update addresses this vulnerability by correcting how the Windows kernel-mode driver handles objects in memory.

Official references

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