This indicates an attempt to remote access Android ADB Debug Port.
Android has a feature called Android Debug Bridge (ADB) which enables developers to remotely debug a device and execute commands.
Some vendors have shipped products with Android Debug Bridge enabled. It listens on port 5555 and allows anybody to connect over the internet to the device and take full control.
Android products with Android Debug Bridge enabled
System Compromise: Remote attackers can gain control of vulnerable systems.
Disable Android Debug Bridge in the device.