TP-Link Omada ER605 Reliance on Security Through Obscurity Vulnerability. This vulnerability allows network-adjacent attackers to access or spoof DDNS messages on affected installations of TP-Link Omada ER605 routers. Authentication is not required to exploit this vulnerability. However, devices are vulnerable only if configured to use the Comexe DDNS service. The specific flaw exists within the cmxddnsd executable. The issue results from reliance on obscurity to secure network data. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of root. Was ZDI-CAN-22439.
The product uses a protection mechanism whose strength depends heavily on its obscurity, such that knowledge of its algorithms or key data is sufficient to defeat the mechanism.