Backstory: I have a Huawei HG8245 router in my house and I want to change the default username/password. I've tried following this guide but the config file always gets reset. My ISP isn't helping either so I'm looking for other ways to accomplish this. The router has telnet access so this seems like a way to change the credentials.
The first shell I gain access to looks like this:
Pressing "?" gives me a list of available commands which I've pasted here, the two interesting ones are "su" and "shell". I can't seem to get su access, even after logging in as root (challenge password prompt, and then nothing happens), but shell gives me a proper linux shell.
WAP>shell BusyBox v1.18.4 (2017-12-26 17:06:34 CST) built-in shell (ash) Enter 'help' for a list of built-in commands. WAP(Dopra Linux) #
Now this is where it gets interesting, BusyBox is installed, but the help command doesn't actually work.
WAP(Dopra Linux) # help ERROR::Command is not existed
Hitting "?" again gives me another list of available commands which I've pasted here. They are pretty limited but I have access to ls and I can see that /bin actually has a lot of classic linux stuff in it, but I can't seem to run any of it, even busybox. It just throws the cheeky "Command is not existed" error message.
My question is: How can I access these commands (preferably cat and echo)?