JVN#17127920: Smart TV Box fails to restrict access permissions

Smart TV Box provided by KDDI CORPORATION enables access to Android Debug Bridge via port 5555/TCP of LAN side interface.
When a cable television provider sets up Smart TV Box at an individual residence, direct access from outside to the LAN side interface of Smart TV Box is disabled. However if the original setting is changed later, for example, LAN side interface connection to internet directly is enabled, access to Android Debug Bridge via port 5555/TCP of LAN side interface becomes enabled. As a result, arbitrary operations without users intent becomes possible, and a remote attacker may conduct arbitrary operations on the device (CWE-284).

Impact

A remote attacker may conduct arbitrary operations on the device without user’s intent, such as installing arbitrary software or changing the device settings.

Solution

Update the Firmware
Update the firmware to the latest version according to the information provided by the developer.

The developer also suggests that a user should check the appropriate network settings of the device by following the guidance provided by the developer.

Products Affected

• Smart TV Box firmware version prior to 1300