#VU25980 Input validation error in Windows and Windows Server - CVE-2020-0796

Vulnerability identifier: #VU25980

Vulnerability risk: High

CVSSv4.0: 8.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Amber]

CVE-ID: CVE-2020-0796

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: Yes

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 execute arbitrary code on the target system.

The vulnerability exists in the way that the Microsoft Server Message Block 3.1.1 (SMBv3) protocol handles certain requests. A remote attacker can trick a client to connect to a malicious SMB server and execute arbitrary code on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Windows: 10 1903 10.0.18362.116, 10 1909 10.0.18363.476

Windows Server: 2019 1903 - 2019 1909

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External links
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200005
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0796
https://github.com/Dhoomralochana/Scanners-for-CVE-2020-0796-Testing
https://github.com/ClarotyICS/CVE2020-0796

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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?

Yes. This vulnerability is being exploited in the wild.