3.6 Fully document and implement all key- management processes and procedures for cryptographic keys used for encryption of cardholder data, including the following:
Note: Numerous industry standards for key management are available from various resources including NIST, which can be found at http://csrc.nist.gov.
3.6.a Additional testing procedure for service provider assessments only: If the service provider shares keys with their customers for transmission or storage of cardholder data, examine the documentation that the service provider provides to their customers to verify that it includes guidance on how to securely transmit, store, and update customers’ keys, in accordance with Requirements 3.6.1 through 3.6.8 below.
3.6.b Examine the key-management procedures and processes for keys used for encryption of cardholder data and perform the following:
The manner in which cryptographic keys are managed is a critical part of the continued security of the encryption solution. A good key- management process, whether it is manual or automated as part of the encryption product, is based on industry standards and addresses all key elements at 3.6.1 through 3.6.8.
Providing guidance to customers on how to securely transmit, store and update cryptographic keys can help prevent keys from being mismanaged or disclosed to unauthorized entities.
This requirement applies to keys used to encrypt stored cardholder data, and any respective key- encrypting keys.
Note: Testing Procedure 3.6.a is an additional procedure that only applies if the entity being assessed is a service provider.