#VU54723 Buffer overflow in Windows and Windows Server - CVE-2021-31979

Vulnerability identifier: #VU54723

Vulnerability risk: High

CVSSv4.0: 8.5 [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-2021-31979

CWE-ID: CWE-119

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Windows
Operating systems & Components / Operating system
Windows Server
Operating systems & Components / Operating system

Vendor: Microsoft

Description

The vulnerability allows a local user to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in Windows kernel. A local user can run a specially crafted program to trigger memory corruption and execute arbitrary code on the system with elevated privileges.

Note, the vulnerability is being actively exploited in the wild.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Windows: 7, 8.1 RT - 8.1, 10 Gold, 10 Mobile, 10 S, 10 20H2 10.0.19042.572, 10 21H1 10.0.19043.985, 10 1507 10.0.10240.16405, 10 1511 10.0.10586.3, 10 1607 10.0.14393.10, 10 1703 10.0.15063.138, 10 1709 10.0.16299.19, 10 1803 10.0.17134.48, 10 1809 10.0.17763.1, 10 1903 10.0.18362.116, 10 1909 10.0.18363.476, 10 2004 10.0.19041.264, 10

Windows Server: 2008 R2 - 2008, 2012 R2 - 2012, 2016 10.0.14393.10, 2019 10.0.17763.1 - 2019 2004

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External links
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31979

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.