Russian Interference in the 2016 U.S. Elections. Expert Testimony by J. Alex Halderman

"Russian Interference in the 2016 U.S. Elections", Expert Testimony by J. Alex Halderman, Professor of Computer Science, University of Michigan, June 21, 2017, U.S. Senate Select Committee on Intelligence. 

Here are the mains conclusions of the testimony: 

"U.S. Voting Machines Are Vulnerable... Today, the vast majority of 3 votes are cast using one of two computerized methods. Most states and most voters use the first type, called optical scan ballots... The other widely used approach has voters interact directly with a computer, rather than marking a choice on paper. It’s called DRE, or direct-recording electronic, voting.Both optical scanners and DRE voting machines are computers. Under the hood, they’re not so different from your laptop or smartphone, although they tend to use much older technology—sometimes decades out of date... 

Some say the decentralized nature of the U.S. voting system and the fact that voting machines aren’t directly connected to the Internet make changing a state or national election outcome impossible. Unfortunately, that is not true...

This month, we’ve seen reports detailing Russian efforts to target voter registration systems in up to 39 states...

We must start preparing now to better defend our election infrastructure... we know how to accomplish this. Paper ballots, audits, and other straightforward steps can make elections much harder to attack."

My comment: Is Russia the only threat to voting systems and election infrastructures? Probably not. The "insider threat" is another option. Other foreign countries, politically motivated hackers, organized crime... might try to hack national or any other election process.