An improper certificate validation vulnerability was found in ADM while updating the DDNS settings.

The DDNS update function in ADM fails to properly validate the hostname of the DDNS server's TLS/SSL certificate. Although the connection uses HTTPS, an improper validated TLS/SSL certificates allows a remote attacker can intercept the communication to perform a Man-in-the-Middle (MitM) attack, which may obtain the sensitive information of DDNS updating process, including the user's account email, MD5 hashed password, and device serial number.This issue affects ADM: from 4.1.0 through 4.3.3.ROF1, from 5.0.0 through 5.1.1.RCI1.