Permissions, Privileges, and Access Controls in Windows and Windows Server - CVE-2021-43890
Published: November 25, 2021 / Updated: December 14, 2021
Vulnerability identifier: #VU58367
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Amber
CVE-ID: CVE-2021-43890
CWE-ID: CWE-264
Exploitation vector: Local access
Exploit availability:
The vulnerability is being exploited in the wild
Vendor: Microsoft
Affected software:
Windows
Windows Server
Windows
Windows Server
Detailed vulnerability description
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to incorrect permissions in windows installer service. A local user can run a specially crafted program to execute arbitrary code with SYSTEM privileges.
The vulnerability exists due to incomplete patch for #VU58061 (CVE-2021-41379).
Note, the vulnerability is being actively exploited in the wild.
How to mitigate CVE-2021-43890
Install update from vendor's website.