Ryan Ackroyd, 26; Jake Davis, 20; and Mustafa al-Bassam, 18, who was not named until now because of his age, all admitted their involvement in the hacktivist gang's attack spree.
The new feature is immediately available for users and "secret" codes can be accessed via SMS or through the Google Authenticator app.
The biggies are two vulnerabilities in Internet Explorer and a single weakness in Remote Desktop Connection.
