I have a raspberrypi with raspbian and default user and pw (I know, don't shoot me). I setup port fw on my router so that I could ssh to it from an external network. Also because my external IP keeps changing every time I reboot my router I'm using dynamic dns on the pi. After a few months of not using it I tried to ssh to it and my credentials were invalid. Tried the same original credentials loging in directly with the same result.
I've got a feeling that I've been hacked and that someone managed to change my default pw....but how?
1.How easy is it to just try to ssh every public IP on earth with default user and pw?
I'm thinking of plugging the sd card on my pc to try to recover some of the stuff that I had there.
2.What is the risk of plugging in a compromised sd card?
If the hacker did in fact manage to get hold of my Pi.
3. What is the extent of the damage caused by having a hacked machine inside my LAN?
4. How can I make sure that there are no further exploits on my local network?