#VU58084 Improper Null Termination in Siemens products - CVE-2021-31884

Vulnerability identifier: #VU58084

Vulnerability risk: Medium

CVSSv4.0: 6.3 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-31884

CWE-ID: CWE-170

Exploitation vector: Local 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 the DHCP client application assumes the data supplied with the “hostname” DHCP option NULL is terminated. A remote attacker on the local network 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

Nucleus ReadyStart: before 4.1.1

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External links
https://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 local network (LAN).

Is there known malware, which exploits this vulnerability?

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