A network misconfiguration is present in the affected devices, where IPv6 is enabled for the WAN interface by default. However, the firewall restrictions in place for IPv4 traffic are not applied to the WAN interface for IPv6. This allows arbitrary access to services running on the device that may be listening via IPv6, such as the SSH and Telnet servers on ports 22 and 23. The misconfiguration could allow an attacker to interact with services intended only for local network clients.