Log out and login, Facebook users advised

​New Delhi: After Facebook admitted that hackers broke into nearly 50 million users' accounts by stealing their "access tokens" or digital keys, cyber experts on Saturday warned over 2.3 billion users to log out and log back into Facebook, or any of third-party apps that use Facebook login.

Facebook has reset the access tokens of almost 50 million accounts it knew were affected. It has also taken the precautionary step of resetting access tokens for another 40 million accounts that have been subject to "View As" look-up in the last year.

"For now, logging out and back in is all that is necessary. The truly concerned should use this as a reminder and an opportunity to review all of their security and privacy settings on Facebook and all other social media platforms," Chester Wisniewski, Principal Research Scientist with global cyber security major Sophos, said. 

According to Dr Gary McGraw, Vice President of Security Technology, Synopsys (Software Integrity Group), this breach emphasises just how important software security is, and how subtle solid security engineering can be.  "When a feature like 'View As' can be turned on its head into an exploit, it indicates a design problem that led to unanticipated security vulnerability," noted Dr McGraw.