Security researchers have sounded the alarm for millions of Gmail, Facebook, and Amazon users after tracking a sharp increase in activity from hackers trying to break into these popular sites. Experts at antivirus firm Kaspersky recorded a 40% spike in password-hacking attempts compared with last year. Facebook, Amazon, and Google accounts are the most sought-after as they help hackers with credit card fraud, identity theft, and malware distribution. View Deal | Get started for FREE with 1PasswordView Deal | Save 56% on all-in-one security package by BitdefenderView Deal | Store passwords and …