Check if there is any other connection: netstat -antup
Check home directory for any more information: ls -lahR /home
Check if there is GUI interface: pidof X (if yes can try to find web browser with any loot (e.g. history, saved passwords, homepage etc), or “recently opened” applications/files)
Search password related file in current path, recursive: grep -R 'password'.
Search file: find / -type f -name "network-secret.txt"
After root access, can change local password via: passwd username