The situation of the COVID-19 pandemic has drastically changed the way companies work today in the current scenario. With many organizations still working remotely, it has exposed them to several new risks and cyber threats. Besides, the increased use of cloud platforms supporting various devices and networks has opened doors for attacks and account infiltrations.
Working in an uncontrolled environment with limited security measures in place turns out to be a completely different challenge for organizations to now deal with. Especially, retail businesses who have always been a soft target to sophisticated cybercrimes, find it challenging to ensure security and maintain PCI Compliance in the remote working scenario.
However, implementing Zero Trust Principles in the PCI Compliance program will address this issue and ensure high-level security against various cyber-attacks. Zero Trust Principle is a proactive defense mechanism that strengthens and broadens the security perimeters to even the remote work process.
It further helps ensure that organizations are compliant with various Data Security and Privacy standards. Elaborating more on this we have explained how organizations can implement Zero Trust Principles in PCI DSS and improve the compliance program. But before that, let us first learn a bit about the Zero Trust Principles and techniques of implementing them in the PCI Compliance program.
What is the Zero Trust Principle?
Zero Trust Principles is a defense mechanism that can strengthen the security posture of your systems and infrastructure. The security model works on a simple premise or assumption that your organization’s IT infrastructure and network are always hostile and exposed to both internal and external threats at all times. So, the security model works on “never trust and always verify” principles that ensure limited access that is further password-protected, verified, and authenticated. The architecture of this security model is based on the key principles around which the security measures must be implemented.
Visibility
You need to have clear visibility of all devices, networks, systems, and user access granted to secure your organization’s IT Infrastructure. This requires you to understand the security posture of the entire Infrastructure including the firewall and antivirus status, OS patch, screen-locks, biometrics, encryptions, physical locks, implemented. Further, constant monitoring of these elements is crucial to secure the infrastructure thoroughly.
Such information will help build an inventory of all endpoint devices and further ease the administrative process for monitoring devices and addressing gaps in security systems. So, any case of unusual activity detected will get immediately flagged and tracking of all the activity will undertake in real-time. This will further facilitate comprehensive security checks.
Access Control
Zero Trust Principle calls for strict controls on access to critical systems, applications, and networks. The principle requires every device to be authorized and constantly monitored to ensure no device is compromised. Implementing stringent access controls is the key requirement in Zero Trust Principles. This helps minimize the attack surface on the network. Administrators must implement strict access controls and enforce the same through adaptive role-based access policies. This will help you stay ahead of the threat actors trying to gain unauthorized access.
Access Verification
Zero trust means no trust without verification. So, verification is the key factor of security that must be applied to all critical assets, systems, and networks. You need to at all times keep a track of authentication and authorization of all access requests to ensure stronger security in your organization.
Implementing multi-factor authentication (MFA) security control is necessary to ensure the establishment of best security practices. Simply relying on passwords cannot ensure security in today’s evolving threat landscape. Constant monitoring and verification will strengthen the defense against the evolving cyber risks.
Least Privilege
Another significant zero trust principle is the least privilege access. This simply means providing users limited access based on their requirements and day-to-day roles and responsibilities. The permission granted for access should also be authenticated, verified, logged, and monitored constantly.
It is a widely adopted cybersecurity measure and an industry-best security practice that helps protect sensitive data and networks. Implementing least privilege is a fundamental step towards protecting privileged access to high-value and sensitive data and assets. This helps minimize the exposure to sensitive data and networks.
Segmentation
Zero Trust Principles call for segmentation or micro-segmentation of networks. To strengthen the security perimeter, it is important to set boundaries around networks that comprise critical data. So, this way perimeter-based security ensures the least visibility and access/traffic to the network.
This helps monitor and track critical networks at granular levels and ensures strict security around them. This can further be backed by separate access controls established for privilege access. Such network segmentation also requires constant monitoring of granular access control to eliminate risk exposure and excess privileges.
How can Zero Trust Principles be aligned with PCI DSS?
PCI DSS Compliance is a standard designed and established to ensure the implementation of maximum security for protecting sensitive cardholder data in the retail industry. Compliance with PCI DSS requires organizations to implement all the 12 requirements outlined by the PCI Council. However, in the evolving threat landscape merely implementing the 12 PCI DSS requirements will not suffice the security requirement. This is when and why integrating the Zero trust principles to seal the security controls to an advanced level is required. Explaining this we have shared how Zero Trust Principles can be applied to PCI DSS applied for ensuring maximum protection.
| PCI DSS v3.2.1 | PCI DSS v4.0 |
|---|---|
| PCI DSS v3.2.1 Requirement 6.5.1 – 6.5.10 | PCI DSS v4.0 Requirement 6.2.4 emphasizes a holistic approach to software security, requiring organizations to prevent: |
| 6.5.1 Injection Flaws: | Injection Attacks: |
| - Prevent attacks where hackers modify code in your system with bad data. | - Prevent attackers from sneaking malicious commands into your system by masquerading them as normal data (e.g., injecting SQL code into a website form). |
| - Validate all user input to block tampering attempts. | Attacks on Data Structures: |
| - Use database safeguards (parameterized queries) to stop injections. | - Prevent attackers from manipulating memory in ways that allow them to run unauthorized code (e.g., buffer overflows). |
| 6.5.2 Buffer Overflows: | Attacks on Cryptography Usage: |
| - Prevent memory misuse attackers can exploit to run malicious code. | - Protect against attempts to break weak encryption, flawed implementations, or exploit vulnerable cryptographic modes. |
| - Check memory boundaries when handling data. | Attacks on Business Logic: |
| - Limit the length of data your system accepts. | - Prevent attackers from abusing application functions designed for normal use (e.g., manipulating client-side web code, circumventing API safeguards, exploiting features beyond their intended purposes). This includes attacks like XSS and CSRF. |
| 6.5.3 Insecure Cryptographic Storage: | Attacks on Access Control: |
| - Protect encryption keys and sensitive data they can access. | - Securely implement login systems, permissions checks, and any mechanism responsible for granting users access - attackers exploit flaws here to gain unauthorized control. |
| - Use strong encryption, prevent flawed implementations. | High-Risk Vulnerabilities: |
| 6.5.5 Improper Error Handling: | - Prevent any serious weaknesses known within your system as discovered in the vulnerability process outlined in Requirement 6.3.1. |
| - Don't give away system details with specific error messages. | |
| - Show users generic errors to prevent information leaks attackers can exploit. | |
| 6.5.6 High-Risk Vulnerabilities: | |
| - Fix serious weaknesses ASAP that attackers could use to harm your system. | |
| - Identify weaknesses: See PCI DSS Requirement 6.1 for this process. | |
| 6.5.7 Cross-Site Scripting (XSS): | |
| - Stop attackers injecting code into your websites that can harm users. | |
| - Validate and sanitize data coming from users, don't include it directly. | |
| 6.5.8 Improper Access Control: | |
| - Prevent unauthorized access to system data and functions. | |
| - Check user rights at every access point. | |
| - Secure file and code to stop users bypassing website checks. | |
| 6.5.9 Cross-Site Request Forgery (CSRF): | |
| - Stop websites tricking users into performing actions they don't mean to. | |
| - Don't rely solely on cookies for authorization, add further checks. | |
| 6.5.10 Broken Authentication and Session Management: | |
| - Protect user sessions from hijacking. | |
| - Secure cookies, prevent exposing session IDs, timeout inactive sessions. |
Conclusion
The Zero trust principle strengthens the security control measures implemented as per PCI DSS requirements. It adds a layer of security to the PCI security control requirements. This further cements the defense systems of the organizations. Implementing these principles will also secure the organization against unknown internal threats that are often neglected. Integrating Zero trust principles in PCI DSS significantly reduces the growing risk exposure and makes the compliance process more achievable. Overall, integrating PCI DSS and Zero Trust Principle provides an effective strategy for robust security and network resilience.
Hope this blog was informative and helps your organization build a strong security defense. Do share your feedback and thoughts on the same and let us know your opinion on the idea of integrating PCI DSS and the Zero Trust Principle.
Narendra Sahoo (PCI QPA, PCI QSA, PCI SSF ASSESSOR, CISSP, CISA, CRISC, 27001 LA) is the Founder and Director of VISTA InfoSec, a global Information Security Consulting firm, based in the US, Singapore & India. Mr. Sahoo holds more than 25 years of experience in the IT Industry, with expertise in Information Risk Consulting, Assessment, & Compliance services. VISTA InfoSec specializes in Information Security audit, consulting and certification services which include GDPR, HIPAA, CCPA, NESA, MAS-TRM, PCI DSS Compliance & Audit, PCI PIN, SOC2 Compliance & Audit, PDPA, PDPB to name a few. The company has for years (since 2004) worked with organizations across the globe to address the Regulatory and Information Security challenges in their industry. VISTA InfoSec has been instrumental in helping top multinational companies achieve compliance and secure their IT infrastructure.
