An issue was discovered in D-Link devices, where a custom daemon runs on UDP port 5978, handling a custom D-Link UDP-based protocol. This protocol allows D-Link mobile and desktop applications to discover devices on the local network. The binary processes received UDP packets in the `main` function, which contains a block of code that performs an unbounded copy operation, allowing a buffer overflow. The custom protocol follows a specific pattern, including `Packetlen`, `Type of packet`, `M` for MAC address, `D` for device type, `C` for base64 encoded command string, and `test`. The insecure copy operation using the `strcpy` function at address `0x0000DC88` results in overflowing the stack pointer after 1060 characters, allowing control of the PC register and resulting in code execution. A third-party application on the device can execute commands without authentication by sending a single UDP packet with custom base64 encoding.