The NPort IA5000A Series devices use Telnet as one of the network device management services. Telnet does not support the encryption of client-server communications, making it vulnerable to Man-in-the-Middle attacks.
Source: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-27184
Reference (s):
- https://ics-cert.kaspersky.com/advisories/klcert-advisories/2021/05/11/klcert-20-020,
- URL: https://ics-cert.kaspersky.com/advisories/klcert-advisories/2021/05/11/klcert-20-020,
- https://www.moxa.com/en/support/product-support/security-advisory/nport-ia5000a-serial-device-servers-vulnerabilities
- URL: https://www.moxa.com/en/support/product-support/security-advisory/nport-ia5000a-serial-device-servers-vulnerabilities