Facebook Inc said it has resolved a glitch that exposed passwords of millions of users stored in readable format within its internal systems to its employees.
The passwords were accessible to as many as 20,000 Facebook employees and dated back as early as 2012, cyber security blog KrebsOnSecurity, which first reported the issue, said in its report.
KrebsOnSecurity, citing a senior Facebook employee, said an internal investigation by the company so far indicates that between 200 million and 600 million Facebook users may have had their account passwords stored in plain text.