The head of an American cyber security firm released a new report highlighting the most vulnerable states for an election computer hack. At the top of the list is Pennsylvania.

According to the report, prepared by Carbon Black, Pennsylvania is vulnerable because of its voting systems. With just over a month away, elections offices around the state and country are preparing.

“We are urging the states just to make sure that their deadbolts are thrown and their locks are on,” FBI Director James Comey said in a recent testimony in front of congress.

Carbon Black blames the outdated computer systems for the vulnerability in Pennsylvania. Professor Rob D’Ovidio is a cyber security expert with Drexel University and read the entire report. He says many, not all, precincts in Pennsylvania use computer equipment without a backup paper trail.