Cybercriminals are trying to make an extra buck by tricking unsuspecting users into buying an antivirus from them for $500 (370). A few months ago, Malwarebytes researchers came across a browser-based FBI ransomware designed to trick victims into paying a so-called fine for accessing illegal content online. Later, the same cybercrooks started demanding more money from internauts who wanted to have their criminal records deleted. Now, theyrs…