CVE-2020-1054

CVE-2020-1054 is a high-severity (CVSS 7.0) vulnerability in Microsoft Win32k. CISA added it to the Known Exploited Vulnerabilities catalog on November 3, 2021, which means exploitation in the wild has been confirmed; US federal agencies had to remediate it by May 3, 2022. CISA does not currently list it as used in ransomware campaigns. Microsoft has 390 vulnerabilities in the KEV catalog, 117 of them linked to ransomware.

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 vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2020-1054
• http://packetstormsecurity.com/files/160515/Microsoft-Windows-DrawIconEx-Local-Privilege-Escalation.html
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1054
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-1054