I am capturing information in a number of plugins (contact form 7, event espresso, etc) and I want to have that data saved into the CMS in an encrypted format. (Not hashing, which is one-way) I would then have the admin login and provide the password to decrypt that data (to be displayed in the CMS admin interface). How would I do this?
Is there a plugin to encrypt data stored in WordPress?
You can just use mcrypt_encrypt() while storing and mcrypt_decrypt() (with corresponding parameters) for reading data. It is really easy to use and straight forward – plus it is a battle-tested encryption package that has no (known) encryption flaws when used correctly.