A leaked intelligence document outlining alleged attempts by Russian military intelligence to hack into U.S. election systems is the latest evidence suggesting a broad and sophisticated foreign attack on the integrity of the nation’s elections. And it underscores the contention of security experts and computer scientists that the highly decentralized, often ramshackle U.S. election system remains profoundly vulnerable to trickery or sabotage. The document, purportedly produced by the U.S. National Security Agency, does not indicate whether actual vote-tampering occurred. But it adds significant new detail to previous U.S. intelligence assessments that alleged Russia-backed hackers had compromised elements of America’s electoral machinery. It also suggests that attackers may also have been laying groundwork for future subversive activity. The operation described in the document could have given attackers “a foothold into the IT systems of elections offices around the country that they could use to infect machines and launch a vote-stealing attack,” said J. Alex Halderman, a University of Michigan computer scientist. “We don’t have evidence that that happened,” he said, “but that’s a very real possibility.”
Computer scientists have proven in the lab that once sophisticated attackers are inside an election network, they could manipulate pre-election programming of its systems and alter results without leaving a trace.
… Iowa University’s Douglas Jones is among computer scientists who say voter registration systems are particularly vulnerable to tampering, in part because they are on the internet.
Someone trying to cause chaos and discredit an election could delete names from registration rolls prior to voting — or request absentee ballots en masse. In the latter case, a voter showing up at the polls on Election Day would be recorded as having already cast their ballot. That could force voters to file provisional ballots, and provoke long lines.