Vulnerability identifier: #VU58086

Vulnerability risk: High

CVSSv3.1: 8.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-31886

CWE-ID: CWE-170

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Nucleus NET
Server applications / Other server solutions
Nucleus Source Code
Server applications / Other server solutions
Capital VSTAR
Server applications / Other server solutions
Nucleus ReadyStart
Server applications / Other server solutions

Vendor: Siemens

Description

The vulnerability allows a remote attacker to execute arbitrary code on the system.

The vulnerability exists due to improper null termination when the FTP server does not properly validate the length of the “USER” command. A remote attacker can execute arbitrary code on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Nucleus NET: All versions

Nucleus Source Code: All versions

Capital VSTAR: All versions

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External links
http://cert-portal.siemens.com/productcert/pdf/ssa-044112.pdf

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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.