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UK Cyber Defence
VulnerabilityAnalyzed

CVE-2020-1054

Microsoft Win32k Privilege Escalation Vulnerability

KEVHIGH 7.0EPSS 54.2%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 3 May 2022). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

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.

CVSS 3.1
7.0 HIGHCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
54.16% probability · 99th percentile
CISA KEV
Listed 3 November 2021 · due 3 May 2022
Weakness
CWE-787
Affected
microsoft/windows 10 1507 · microsoft/windows 10 1607 · microsoft/windows 10 1709 · microsoft/windows 10 1803 · microsoft/windows 10 1809 · microsoft/windows 10 1903 · microsoft/windows 10 1909 · microsoft/windows 7 · microsoft/windows 8.1 · microsoft/windows rt 8.1 · microsoft/windows server 1803 · microsoft/windows server 1903 · microsoft/windows server 1909 · microsoft/windows server 2008 · microsoft/windows server 2012 · microsoft/windows server 2016 · microsoft/windows server 2019
Source
secure@microsoft.com

CISA notes

Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2020-1054

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.