Federal prosecutors in California have filed criminal charges against four employees of Adconion Direct, an email advertising firm, alleging they unlawfully hijacked vast swaths of Internet addresses and used them in large-scale spam campaigns. KrebsOnSecurity has learned that the charges are likely just the opening salvo in a much larger, ongoing federal investigation into the companys commercial email practices. All four men have pleaded not guilty to the charges, which stem from a grand jury indictment handed down in June 2017.”]