PolygamousRanchKid writes with news that staffers for the Bernie Sanders campaign improperly viewed the voter data gathered by Hillary Clinton's campaign by exploiting a software error. "The discovery sparked alarm at the DNC, which promptly shut off the Sanders campaign's access to the strategically crucial list of likely Democratic voters. The DNC maintains the master list and rents it to national and state campaigns, which then add their own, proprietary information gathered by field workers and volunteers. Firewalls are supposed to prevent campaigns from viewing data gathered by their rivals." On Wednesday, while the software was being patched, it briefly opened access to all of the restricted voter data. The Sanders campaign fired the staffer responsible for viewing the data, Josh Uretsky. The campaign says their access was simply part of an investigation to determine their own exposure, and blames the vendor (and those who hired it) for improperly securing the data.