#VU72195 Input validation error in Windows and Windows Server - CVE-2023-21689

Vulnerability identifier: #VU72195

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2023-21689

CWE-ID: CWE-20

Exploitation vector: Network

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 remote attacker to compromise the affected system.

The vulnerability exists due to insufficient validation of user-supplied input in Microsoft Protected Extensible Authentication Protocol (PEAP). A remote attacker can send specially crafted PEAP packets to the system and execute arbitrary code.

Successful exploitation of the vulnerability requires that NPS is running on the Windows Server and has a network policy configured that allows PEAP.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Windows: 10 Gold, 10 Mobile, 10 S, 10 20H2 10.0.19042.572, 10 21H1 10.0.19043.985, 10 21H2 10.0.19044.1288, 10 22H2 10.0.19045.2130, 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 1706, 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, 11 21H2 10.0.22000.194, 11 22H2 10.0.22621.521, 11

Windows Server: 2008 R2, 2012 R2 - 2012, 2016 10.0.14393.10, 2019 10.0.17763.1 - 2019 2004, 2022 10.0.20348.202 - 2022 20H2

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External links
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21689

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.