If you have an account with GEDMatch, you may have already gotten an email regarding this, but here is an article that will tell you more. (As of the morning of July 24, 2020, the site was still down.)
Over the weekend, a security breach changed the permission settings on millions of profiles in GEDmatch, a DNA database used by genealogists. For three hours, DNA profiles were visible to all members, including law enforcement agencies, which sometimes use the site to find partial matches to crime scene DNA.... [read more]