CVE-2020-1054: Microsoft Win32k Privilege Escalation Vulnerability

CISA Known Exploited Vulnerabilities

Name

Microsoft Win32k Privilege Escalation Vulnerability

Vendor

Microsoft

Product

Win32k

Added to the catalog

2021-11-03

Due date for US federal agencies

2022-05-03

Weaknesses

CWE-787

Catalog version

2026.10.30

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 (CISA)

Apply updates per vendor instructions.

Ransomware use: CISA does not mark known use of this vulnerability in ransomware campaigns.

Links in CISA's notes

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

Read on 2026-11-02T23:39:54.475Z under licence cisa-kev-cc0@b0067899 from https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

NVD analysis

Status

Analyzed

Published

2020-05-21T23:15:12.070

Last modified

2026-10-08T10:36:00.860

Weaknesses

CWE-787

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.

References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2020-1054 (Patch, Vendor Advisory)
• http://packetstormsecurity.com/files/160515/Microsoft-Windows-DrawIconEx-Local-Privilege-Escalation.html (Exploit, Third Party Advisory, VDB Entry)
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1054 (Patch, Vendor Advisory)
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-1054 (US Government Resource)

This product uses the NVD API but is not endorsed or certified by the NVD.

Read on 2026-11-02T23:41:51.476Z under licence nvd-api-terms-of-use@ff2a5288 from https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2020-1054

CVE record

Title (CNA)

Win32k Elevation of Privilege Vulnerability

Assigner

microsoft

State

PUBLISHED

Published

2020-05-21T22:52:50.000Z

Updated

2026-10-07T17:30:41.211Z

Problem types

Elevation of Privilege

References

• Win32k Elevation of Privilege Vulnerability

Read on 2026-11-03T01:03:09.674Z under licence cve-terms-of-use@81bfa2f3 from https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2020/1xxx/CVE-2020-1054.json

Defensive techniques (MITRE D3FEND)

D3FEND maps these defensive techniques to the weakness (CWE) that NVD lists for this CVE, through the digital artifacts the weakness affects. D3FEND does not say they stop this vulnerability.

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