An authentication bypass vulnerability in the /web/um_open_telnet.cgi endpoint in Nexxt Solutions NCM-X1800 Mesh Router firmware UV1.2.7 and below, allowing an attacker to remotely enable the Telnet service without authentication, bypassing security controls. The Telnet server is then accessible with hard-coded credentials, allowing attackers to gain administrative shell access and execute arbitrary commands on the device.
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.