SSL Needs to Go
The PCI Security Standards Council has notified security professionals that the SSL protocol (any version) no longer meets the definition of "strong cryptography" as outlined in the PCI standards and a new approach will need to be taken to protect payment transactions and cardholder data. Currently, TLS versions 1.1 and 1.2 meet the "strong cryptography" standard.
A new version of the PCI DSS (v3.1) will be released in April 2015. The "strong cryptography" requirement will become effective immediately but will have a sunset provision to allow organizations time to remove SSL from their networks by June 30, 2016. At this time we do not know the specifics regarding the actual sunset date. For this reason we highly recommend that any cryptography used to protect payment transactions and cardholder data be updated to meet the standard as soon as possible.
The Security Standards Council has provided a brief FAQ on this transition:
Why SSL needs to be removed
The National Institute of Standards and Technology (NIST) has identified the Secure Socket Layers (SSL) v3.0 protocol, a cryptographic protocol designed to provide secure communications over a computer network, as not acceptable for the protection of data due to inherent weaknesses within the protocol. Because of these weaknesses, no version of the SSL protocol meets the PCI Security Standards Council (PCI SSC) definition of “strong cryptography,” and revisions to the PCI Data Security Standard (PCI DSS) and the Payment Application Data Security Standard (PA-DSS) are necessary.
The successor protocol to SSL is TLS (Transport Layer Security) and its most current version as of this publication is TLS 1.2. TLS 1.2 currently meets the PCI SSC definition of “strong cryptography”.
Risk to payment card data
The SSL protocol vulnerability primarily affects web servers and browsers, so if exploited it can jeopardize the security of any payment card data being accepted or processed. Upgrading to a current, secure version of TLS, the successor protocol to SSL, is the only known way to remediate the SSL vulnerabilities that have been most recently exploited by browser attacks including POODLE and BEAST.
Effect on PIN Transactions
PIN Transaction Security at Point of Interaction terminals (devices such as a magnetic card readers and chip card readers that enable a consumer to use a payment card to make a purchase) can be impacted if the software on these terminals is communicating using the SSL protocol. Known vulnerabilities are difficult to exploit in this environment so the PCI Council considers this a lower priority risk compared to web servers and browsers. Organizations will need to remain up-to-date with vulnerability trends to determine whether or not they are susceptible to any known exploits. New threats and risks must continue to be managed in accordance with applicable PCI DSS Requirements, such as 6.1, 6.2, and 11.2.
The changes impact all requirements in the PCI DSS and PA-DSS that reference SSL as an example of “strong cryptography”. Specifically:
- PCI DSS Requirements 2.2.3, 2.3 and 4.1
- PA-DSS Requirements 6.2, 8.2, 11.1 and 12.1-12.2
All PCI DSS and PA-DSS v3.0 documentation will be affected, including: Self-Assessment Questionnaires (SAQ), Attestation of Compliance (AOC), and Report on Compliance (ROC), Attestation of Validation (AOV) and Report on Validation (ROV).
The PA-DSS revision will be released shortly and a summary of the changes will be shared with PCI participating organizations and assessors in advance of publication.
When published, the revisions will be effective immediately but impacted requirements will have a sunset date to let organizations with affected systems implement the changes. The Council will provide guidance on risk mitigation approaches to be applied during the migration process.
The PCI Council urges organizations to work with your IT departments and partners to understand if and how your systems are using SSL and to determine available options for upgrading to TLS 1.1 or higher as soon as possible.
When publishing the revisions, the Council will also provide guidance and educational webinars on the use of interim risk mitigation approaches, migration recommendations and alternative options for strong cryptographic protocols.
Additional information will be posted, as it becomes available, as an addendum to the PCI SSC Bulletin on Impending Revisions to PCI DSS, PA-DSS previously published in February of this year.
Please don't hesitate to contact the Masergy Professional Services team at any time if you have any questions.