According to Verified voting, "voted ballots sent via Internet simply cannot be made secure and make easy and inviting targets for attackers ranging from lone hackers to foreign governments seeking to undermine US elections."
"In total, the vulnerabilities investigators found were so severe and so trivial to exploit, Epstein noted that “anyone with even a modicum of training could have succeeded” in hacking them. An attacker wouldn’t have needed to be inside a polling place either to subvert an election... someone 'within a half mile with a rudimentary antenna built using a Pringles can could also have attacked them."
"What the scientists have in their briefcases is terrifying." -- Nikita Khrushchev