The remote web server does not set an X-Frame-Options response header or a Content-Security-Policy 'frame-ancestors' response header in all content responses. This could expose the site to a clickjacking or UI redress attack, in which an attacker can trick a user into clicking an area of the vulnerable page that is different than what the user perceives the page to be. This can result in a user performing fraudulent or malicious transactions. (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-252213-security-enhancement-web-application-potentially-vulnerable-to-clickjacking