It is critical for payment card industry (PCI) organizations to protect cardholder data (CHD) integrity throughout processing, storage, and transmission. Specifically, PCI compliance network security can help minimize the risks of CHD breaches during processing and transmission across web applications and networks. Recent data breaches highlight the need for PCI organizations to address the exploitable network security vulnerabilities that could potentially compromise CHD integrity. Read on to learn more about how to address these vulnerabilities via PCI compliance network requirements.
How to Achieve PCI Compliance Network Security
The PCI Security Standards Council established guidelines, such as the PCI Data Security Standards, to protect customers’ sensitive card information. To achieve PCI compliance, network security must be robust.
Pertaining to network security, the most critical PCI compliance network requirements are:
- Maintaining secure networks
- Encrypting open network transmissions
- Testing critical networks
Developing robust PCI compliance network security can protect your organization from any unforeseen threats to valuable customer data.
Securing Networks via PCI DSS Firewall Requirements
PCI DSS Requirement 1 necessitates that organizations processing card payments implement appropriate firewall configurations to protect CHD integrity. Firewalls constitute one of the most basic and essential elements of network security. By monitoring and filtering all network traffic, your cybersecurity infrastructure helps prevent threats from materializing into attacks.
Your organization can leverage firewalls to maintain a secure CHD environment and achieve PCI compliance network security by:
- Implementing secure firewall and router configurations – Establishing firewall and router configuration standards helps secure the flow of network traffic into and out of the CHD environment. Some of the critical components of these standards include:
- Establishing formal processes to test changes in configurations and any associated network connections
- Documenting connections between internal and external networks (including wireless networks) and CHD environments
- Diagrammatically representing the flow of CHD across networks
- Establishing firewalls for all internet connections within both internal and external networks
- Structuring network management, specifically the roles and responsibilities of management personnel
- Documenting business-use decision-making processes pertaining to services, security features, and the definitions of insecure protocols
- Reviewing existing configurations on a six-month basis
- Building restrictive firewall and router configurations – The configurations your security team establishes must be sufficiently restrictive to identify and prevent malicious activity. All traffic from untrusted networks should be restricted, regardless of the data access and actions attempted. CHD environment (CDE) configurations should only allow access for necessary protocols.
- Preventing direct access of public networks to the CHD environment – Preventing any unauthorized internet access to the CHD environment restricts malicious traffic intrusion. It’s also required under the PCI DSS wireless guidelines. Some of the applicable restrictive security measures include:
- Limiting traffic inflow to only those system components providing authorized and publicly accessible ports, protocols, or services via a demilitarized zone (DMZ)
- Routing inbound traffic to only those IP addresses in the DMZ
- Detecting and blocking spoofing attempts via forged IP addresses, such as internet traffic with an internal address
- Preventing any unauthorized traffic flowing from the CHD environment to the internet
- Setting permissions to allow network access only if from a trusted, authorized source
- Securing and segmenting system components, such as those storing CHD, in internal network zones, away from the DMZ and untrusted networks
- Preventing unauthorized disclosures of routing information and private IP addresses
- Installing firewall functionality on personal-use devices – Employee-use of personal devices outside of secured networks present risks to CHD environments. Installing personal firewall software and other such functionalities should ensure that the firewall configurations are:
- Actively and consistently running
- Not altered by the device users
- Specifically defined for personal-use devices
- Documenting policies and processes – Operational procedures and security policies must be documented and made available, ensuring that all affected parties are aware of the defined scopes and relevant applications.
Implementing the security controls stipulated by the PCI DSS firewall requirements can protect sensitive cardholder environments from cyber threats while also achieving PCI compliance network security.
PCI Compliance Network Security via Encrypted CHD Transmission
Transmitting CHD over open public networks presents severe vulnerabilities and hacking risks, underscoring the need for data encryption for PCI compliance network security. Specifically, the processing of card payments via web applications can render unencrypted data vulnerable to cyberthreats.
Via encryption, your organization can safeguard CHD transmission and meet PCI compliance network requirements in several ways, the most critical of which include:
- Strengthening cryptographic and security controls – CHD transmitted over open public networks—such as the internet, wireless and cellular technologies—and satellite communication should be appropriately secured, using industry best practices and verifying the use of:
- Trusted keys and security certificates
- Secure protocol versions or configurations
- Encryption protocols with appropriate encryption strengths
- Limiting the use of end-user applications for transmitting CHD – Unprotected primary account numbers (PANs) should not be transmitted over end-user messaging applications, including but not limited to email, SMS, or instant messaging to prevent unauthorized exposure.
- Documentation – The use of all security policies and procedures related to CHD encryption should be documented and relayed to all affected parties. This includes cryptographic key management and defined key expiries. Additionally, any policy updates should be communicated promptly.
Implementing encryption practices to secure the processing and transmission of CHD helps achieve PCI compliance network security and minimizes the risk of data breaches.
Network Testing for PCI Compliance and Security
Besides implementing CHD encryption protocols, another critical PCI compliance network security measure involves testing CHD transmission networks for any vulnerabilities, specifically those introduced to the CHD environment by patch deployment and configuration updates, or lack thereof. To achieve firewall PCI compliance, your organization can implement several network security measures, the most critical of which include:
- Conducting quarterly testing of the CHD environment to detect and identify any wireless access points, both authorized and unauthorized. PCI DSS wireless connection guidelines also suggest inventorying all access points to detect the presence of unauthorized access. Any detection should trigger investigation and analysis, with genuine threats escalated according to the appropriate incident response protocols.
- Conducting network vulnerability scans, both internally and externally, quarterly and following any significant changes to the networks transmitting CHD. Any identified vulnerabilities should be addressed, with rescans conducted as needed to achieve passing scans.
- While any scans conducted following internal scans or network changes can be performed internally, an approved scanning vendor (ASV) must complete the quarterly external scans mandated for PCI DSS compliance.
- Identifying potential network vulnerabilities via penetration testing, both annually and after rolling out significant upgrades or modifications.
- In instances where segmentation reduces the scope of PCI DSS, it is critical for annual penetration testing to ensure the operationality and effectiveness of the employed segmentation methods.
- For service providers utilizing segmentation, penetration testing should be conducted on the controls at least every six months and post-modification to confirm the scope of PCI DSS.
- Detecting network intrusions using robust detection or intrusion prevention methods that can monitor traffic at critical points and the perimeter of CHD environments.
- Sophisticated, real-time threat analysis will alert relevant personnel of these potential threats so they can begin investigating.
- The intrusion detection and prevention system should be frequently updated to ensure optimal detection responses. This is because most systems rely on signature detection to identify threats. Without updates, detection and monitoring tools lack up-to-date threat intelligence.
- Documenting the full scope of security policies and relevant operational procedures, ensuring notification of all affected parties.
Application of network testing processes can help your organization rapidly detect evolving threats while simultaneously achieving PCI compliance network security.
Protect Critical Networks and Valuable Cardholder Data
Protecting sensitive cardholder data from threat actor activity is critical for all organizations processing card payments. It often requires the help of a Qualified Security Assessor (QSA) to guide PCI DSS compliance and an Approved Scanning Vendor (ASV) to conduct external network testing.
As a cybersecurity expert and an SSC-approved third party for assessment and scanning, RSI Security provides the guidance organizations need to streamline compliance.
To learn more about PCI compliance network security, contact RSI Security today for a quick consultation.