Avi Rubin, a computer security expert at Johns Hopkins University, joined Public Radio International’s ‘Science Friday’ program last week for a discussion about the security of U.S. voting systems.

The segment comes on the heels of a massive and well-publicized breach of Democratic National Committee data—a hack widely reported to be linked to Russia. More recently, Republican presidential candidate Donald Trump has suggested that the November election could be “rigged.”

“IF THERE WERE A HACK, … THAT COULD DISENFRANCHISE LARGE NUMBERS OF VOTERS, OR IT COULD EVEN JUST BRING INTO DOUBT WHETHER THE ELECTION WAS RUN FAIRLY.”

Avi Rubin, JHU computer security expert

In light of those events, and with the elections just three months away, just how vulnerable are our voting booths and our voting results?

“Everything we know about electronic voting machines is they’re not very secure, they’re not tested or designed rigorously, and in many cases there’s no way to detect or recover from fraud,” said Bruce Schneier, a cryptographer, computer security specialist, and author of the 2015 book Data and Goliath: The Hidden Battles to Collect Your Data and Control Your World. “So there really is a disaster waiting to happen. We don’t know when it will or if it will, but it’s not pretty.”

Excerpted from the Hub.