Jail is an old HTB machine that is still really nice to play today. There’s a bunch of interesting fundamentals to work through. It starts with a buffer overflow in a jail application that can be exploited to get execution. It’s a very beginner BOF, with stack execution enabled, access to the source, and a way to leak the input buffer address. From there, I’ll abuse an NFS share without user squashing to escalate to the next user. Then there’s an rvim escape to get the next user. And ...
