Storing Credit Card Numbers in SESSION - ways around it?

Question

I am well aware of PCI Compliance so don\'t need an earful about storing CC numbers (and especially CVV nums) within our company database during checkout process.

Howev

Answer 1

Store the card details to any persistence medium (database, whatever), but encrypt the card number with a unique and random key that you store in the session. That way if the session is lost, the key is too - which gives you enough time to clean out expired/abandoned data.

Also make sure your sessions are protected from hijacking. There are hardware solutions to this, but a simple in-code way is to tie the session ID to a hash of the first octet of the IP plus the user agent. Not foolproof but it helps.

Edit: The key bits to minimizing your risk is to make sure you get rid of that info as soon as possible. Right after the transaction goes through, delete the record from the database. You also need a rolling job (say every 5 minutes) that deletes any records older than your session timeout (usually 20 minutes). Also, if you are using a database for this very temporary data, make sure it is not on an automated backup system.

Again, this solution is not foolproof and I am not even 100% sure it is compliant with CC security requirements. However, it should require an attacker have total runtime control of your environment to actively decrypt customer CC info, and if a snapshot of your database is compromised (much more likely/common), only one CC can be brute-forced at a time, which is about the best you can hope for.