The election probably wasn’t hacked — but Ukraine’s history shows how easy it would be

A cybersecurity expert is calling for a recount of the presidential election in three key states because he knows how easy it would be to hack the vote -- and because it's happened before.

J. Alex Halderman, a computer science professor at the University of Michigan, urged Hillary Clinton to call for a forensic audit of the voting machines in Wisconsin, Michigan and Pennsylvania -- three states surprisingly won by Donald Trump.

Hackers linked by U.S. officials to the Russian government attacked the Democratic National Committee, Clinton's campaign chairman, and voter registration systems in Arizona and Illinois, and there's evidence hackers tried to break into election offices in several other states.

Halderman said it would be quite easy for hackers to identify states where polling data suggested a close result, and then install malware in voting machines that would shift a small percentage of the ballots toward a certain candidate.

That malware could be designed to remain inactive -- and thus undetected -- during testing prior to the election, and then erase itself after the polls close, he said.

Halberman cautions that he does not believe a cyberattack caused Trump to perform better in those three states than polls predicted, but he wants Clinton to call for a recount just to be sure.

U.S. voting machines are almost laughably easy to hack into, and pro-Russian hackers who call themselves CyberBerkut maliciously committed acts of "wanton destruction" in 2014 as they attempted to rig Ukraine's national election, according to a Christian Science Monitor report.

Four days before the May 25, 2014, election, the hackers broke into Ukraine's central election computers, where they deleted files, rendered the vote-counting system inoperable and destroyed the network infrastructure, and they proved what they'd done by dumping emails and other documents online.

Government officials were able to repair the damage by the following day using backups, but cyber experts discovered and removed a virus that had been installed on central election computers just 40 minutes before the results were scheduled to be announced live on television.

The malicious software, if it had not been removed in time, would have showed ultra-nationalist Right Sector party leader Dmytro Yarosh as the winner with 37 percent of the vote and Petro Poroshenko, who actually won, with 29 percent.

Russian Channel One aired a bulletin that same night declaring Yarosh had won with -- you guessed it -- 37 percent of the vote.

In actuality, Yarosh garnered just 1 percent of the vote.

But the hackers weren't done.

Early the following morning, after polls had closed and results came in from election districts around the county, internet links submitting those data were hit by a distributed denial of service, or DDoS, attacks.

That blocked election results for about two hours, and an American cybersecurity company linked that DDoS attack to CyberBerkut.

International observers ultimately declared the Ukraine vote had been genuine, but Halderman said the attacks showed how vulnerable electronic voting machines are to tampering.

"I know I may sound like a Luddite for saying so, but most election security experts are with me on this: paper ballots are the best available technology for casting votes," Halderman said.

That's also why a vote audit is necessary, he said.

"The only way to know whether a cyberattack changed the result is to closely examine the available physical evidence — paper ballots and voting equipment in critical states like Wisconsin, Michigan, and Pennsylvania," Halderman said. "Unfortunately, nobody is ever going to examine that evidence unless candidates in those states act now, in the next several days, to petition for recounts."