Unattended terminals

All systems are vulnerable if terminals are left logged in and unattended. The most serious problem occurs when a system manager leaves a terminal unattended that has been enabled with root authority. In general, users should log out anytime they leave their terminals.

You can force a terminal to log out after a period of inactivity by setting the TMOUT and TIMEOUT parameters in the /etc/profile file. The TMOUT parameter works in the ksh (Korn) shell, and the TIMEOUT parameter works in the bsh (Bourne) shell.

The following example, taken from a .profile file, forces the terminal to log out after an hour of inactivity:

TO=3600
echo "Setting Autologout to $TO"
TIMEOUT=$TO
TMOUT=$TO
export TIMEOUT TMOUT