Default password ?
Misleading. A default password is just something that the hardware maker provided because there has to be one - all that needs doing is to change it. In this case, however, the password and the user name are hardcoded and are not changeable. That makes it much more than a default password. That makes it a permanent entry point to anyone who knows that information, which is just about anyone who bothers to look for it.
The team that built this robot were obviously people without even the most basic notion of the definition of security. I mean, how hard can it be to allow for changing the bloody password ?