PCI New Rules: Reading The Tea Leaves

When the PCI Council periodically sends out sanctioned teases about an upcoming version, the fun part is the tea-leaf-like reading of its deliberately vague hints. And the Council has offered us quite a bunch to choose from, including "expanded definition of systems components to include virtual components," "recognize that issuers have a legitimate business need to store sensitive authentication data" and the especially intriguing "update requirement to allow business justification for copy, move and storage of CHD during remote access."

The most powerful change from the hints was a warning that too much encryption may actually weaken network security. (See this week's PCI column from Walt Conway.) But let's delve into some of the more mysterious and intriguing elements first.

  • Scope Of Assessment
    PCI phrasing: "Clarify that all locations and flows of cardholder data should be identified and documented to ensure accurate scoping of cardholder data environment." Interpretation: This is a most welcome change. It should be an explicit requirement to spend time locating all of the sensitive data anywhere in the network--or on PDAs, thumbdrives, iPads, home computers or backup drives--and making sure it complies with all PCI requirements.
  • Virtualization
    PCI phrasing: "Expanded definition of system components to include virtual components. Updated requirement 2.2.1 to clarify intent of 'one primary function per server' and use of virtualization." Interpretation: Expect guidance on what is and is not in scope. As virtualization becomes more common--and complex--some solid operating rules will be essential for expansion confidence.
  • Legitimate Business Need
    PCI Phrasing: "Recognize that Issuers have a legitimate business need to store Sensitive Authentication Data." Interpretation: Hello, hornet's nest. This concept goes beyond the typical compensating control question and allows QSAs to give weight to the legitimate business argument, at least for issuers. Presumably, this concept will be somewhat more stringent than "a business need is to save money and it's cheaper to simply leave that stuff in there." Issuers have quite a few commonsense needs to retain such data, so the exact phrasing will be fascinating. At one extreme, it might have little consequence beyond giving QSAs official cover for what almost all were already doing.
  • Remote Access
    PCI Phrasing: "Update requirement to allow business justification for copy, move and storage of CHD during remote access." Interpretation: Just saying "remote access" is enough to make many QSAs pass out. But acknowledging that retailers have increasing needs for doing almost everything remotely--at times--means that some liberalization of remote cardholder data is inevitable. How far the Council will go is the question.
  • Key Management
    PCI Phrasing: "Clarify processes and increase flexibility for cryptographic key changes, retired or replaced keys and use of split control and dual knowledge." Interpretation: The Council is reinforcing what every security person and QSA knows: The bad guys attack the keys, not the crypto. Expect clarification on hashing standards and more.
  • Hardware
    PCI Phrasing: "Provide further guidance on PA-DSS applicability to hardware terminals." Interpretation: The most interesting potential area here is the smartphone and POS interaction area.