The remote SSH server is configured to allow weak encryption algorithms or no algorithm at all. (Source: Tenable Nessus)
Since this is a medium severity issue, users can assess their environment and schedule the update during the next maintenance or update cycle.
This alert has come from: https://www.moxa.com/en/support/product-support/security-advisory/mpsa-259471-security-enhancement-ssh-weak-algorithms-supported