Approximately 35 Million voter registration records from 20 states have appeared for sale online. These records include Full Name, Phone, Address, Voting History and 'other' data. There have been other larger leaks and breaches of voter registration records in the past (for example, in 2015 191 Million were found to be freely accessible online)
Details including the affected states are available here: https://www.anomali.com/blog/estimated-35-million-voter-records-for-sale-on-popular-hacking-forum [anomali.com]
Why is our voting history retained beyond the current election? This is especially worrisome if you vote in the wrong primaries in an area that has a prevailing opinion that differs sharply from your own.