[O'Murchu] demonstrated the infection of an S7-300 PLC device connected to an
airpump. Using the Step 7 software, he programmed the pump to run for
three seconds, gently inflating a balloon attached to the pump. O'Murchu
then demonstrated how a Stuxnet infected PLC would instruct the pump to
run, instead, for 140 seconds, quickly bursting the balloon.
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