(BELGRADE, Serbia) -- A couple of college students who hope to land jobs in computer security used iPhones to hack into a commercial billboard, played Space Invaders on it for a while, and then sent the billboard's owner a description of how they carried out their stunt.
The thrill of their triumph quickly turned to terror for Ivan Petrovic, 21, and Filip Stanisavljevic, 20, as they were lectured by their parents and professors and were summoned to a meeting this week by the owner of the billboard.
The billboard's owner, however, thanked them for the security lesson and gave them each an iPad Mini.
"We suffered no damage, so we decided to gave them a mini ipad each," Slobodan Bob Petrovic, the owner of DPC, which owns billboards in downtown Belgrade, told ABC News on Friday.
Filip Stanisavljevic and Ivan Petrovic invaded Belgrade's Republic Square March 8 and used their iPhones to take over the electronic billboard. To the amusement of passing pedestrians, they hacked into it and for the next 22 minutes played a large scale version of Space Invaders.
They ended their stunt by putting a message up on the board that read Hacked4Fun, and then alerted the company with a detailed description of the security flaw and how to fix it.
"This has never happened before, but we appreciate the fact that these guys have, in a charming way, pointed us to this huge problem," Slobodan Petrovic told ABC News. "Imagine if someone hacks our billboards to propose to his girlfriend, or just have 10 minutes of glory by posting his picture on all of our billboards."
"Now it is clearer than ever that we need to protect ourselves better. In more developed countries, these actions are unthinkable because of severe sanctions," said Petrovic, who has no relation to the student who hacked his billboard.
Ivan Petrovic said they hijacked the billboard to make a point.
"We are not hackers nor do we participate in any form of hacking," Ivan Petrovic told ABC News. "We are two computer science students who did this for research purposes only, to demonstrate the lack of security in IT systems in general."
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