Vulnerability identifier: #VU58504

Vulnerability risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-35533

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
RTU500 CMU
Hardware solutions / Firmware

Vendor: ABB

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input in the APDU parser of the BCI IEC 60870-5-104 function. A remote attacker can send a specially crafted message and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

RTU500 CMU: 12.0 - 12.4

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External links
http://search.abb.com/library/Download.aspx?DocumentID=8DBD000063&LanguageCode=en&DocumentPartId=&Action=Launch

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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.