Buffer overflow in Windows and Windows Server - CVE-2020-17087
Published: October 31, 2020 / Updated: July 29, 2021
Vulnerability identifier: #VU48060
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-2020-17087
CWE-ID: CWE-119
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 privilege son the system.
The vulnerability exists due to a boundary error within the Windows Kernel Cryptography Driver cng.sys, which exposes a "\Device\CNG" device to user-mode programs and supports a variety of IOCTLs with non-trivial input structures. A local user can run a specially crafted program to trigger memory corruption and execute arbitrary code on the system with elevated privileges.
Note, this vulnerability is being actively exploited in the wild.
How to mitigate CVE-2020-17087
Install update from vendor's website.