I friend my mine wrote a "memoline" messaging system for the HP3000, and everybody used it with those "smart" HP terminals. I knew he had admin privs, and what

I friend my mine wrote a "memoline" messaging system for the HP3000, and everybody used it with those "smart" HP terminals. I knew he had admin privs, and what the command to give me admin privs was, so I sent him a message that said something like: Hi, Frank! How much would I have to pay you to execute the command: % grant Don.Hopkins admin Followed by the HP escape sequences for [up][right][right][send rest of line as input][up]. So when he read the message, it entered the command and ran it with his admin privileges, granting me admin! Lesson: Don't print out raw escape sequences from untrusted messages! And don't design terminals with [send rest of line as input] commands.