A compromised master password renders all of the protected passwords vulnerable. A password policy is a guide to choosing satisfactory passwords. Some computer systems store user passwords as plaintext, against which to compare user logon attempts. These attacks took place in early 2015 and thousands of usernames and passwords stolen. Only the passwords and Secure Notes are encrypted, with Triple DES. Transmissions are protected with high-security encryption and optional passwords. There is specialized software designed to recover lost Microsoft Office passwords on pre-AES encryption. Authentication programs vary in which characters they allow in passwords. They were able to delete torrents and expose users' IP-addresses, emails and MD5-hashed passwords. The breach included the loss of user names, hashed passwords, addresses and e-mails. Apache advised users to change their passwords. This defeats "reusing" hashes in attempts to crack multiple passwords. They can be used as a replacement for user names and passwords. Forward secrecy protects past sessions against future compromises of secret keys or passwords. This version introduced the ability to import data from other browsers, including bookmarks and passwords.