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PCI DSS Payment Card Industry Data Security Standard

💳 PCI DSS: Payment Card Industry Data Security Standard

PCI DSS is a global security standard designed to protect cardholder data and reduce credit card fraud. Any organisation that stores, processes, or transmits cardholder data must comply — making PCI DSS a core concern for cybersecurity teams.

📘 What Is PCI DSS?

The Payment Card Industry Data Security Standard (PCI DSS) is a set of security requirements created to safeguard payment card data.

  • Developed by: PCI Security Standards Council (founded by Visa, MasterCard, American Express, Discover, and JCB)
  • Current version: PCI DSS v4.0 (released March 2022)
  • Purpose: Ensure safe handling of credit card data and prevent breaches

🧭 Why Does PCI DSS Exist?

PCI DSS was introduced to:

  • Prevent payment card fraud
  • Reduce risks caused by weak security in payment systems
  • Standardise security practices across merchants, service providers, and processors

👥 Who Does PCI DSS Affect?

PCI DSS applies to:

🏢 Merchants

Any organisation that accepts card payments — online or in-store — regardless of size or transaction volume.

🔄 Service Providers

Third parties involved in storing, processing, or transmitting cardholder data (e.g. payment gateways, hosting providers, managed service providers).

Note: There is no “PCI certification” for software or platforms — compliance is always the responsibility of the entity handling the card data.

🛡️ What Is Protected Under PCI DSS?

Cardholder Data (CHD):

  • Primary Account Number (PAN)
  • Cardholder name
  • Expiration date
  • Service code

Sensitive Authentication Data (SAD):

  • Full magnetic stripe / chip data
  • CVV/CVC codes
  • PINs and PIN blocks

Storing SAD after authorisation is strictly prohibited.

📋 Core PCI DSS Requirements

PCI DSS includes 12 requirements, grouped into 6 control objectives:

🔐 Build and Maintain a Secure Network

  1. Install and maintain a firewall configuration
  2. Do not use vendor-supplied defaults for system passwords

🔒 Protect Cardholder Data

  1. Protect stored cardholder data
  2. Encrypt transmission of cardholder data across open, public networks

🧑‍💼 Maintain a Vulnerability Management Program

  1. Protect all systems against malware
  2. Develop and maintain secure systems and applications

👥 Implement Strong Access Control Measures

  1. Restrict access to cardholder data by business need-to-know
  2. Identify and authenticate access to system components
  3. Restrict physical access to cardholder data

📊 Regularly Monitor and Test Networks

  1. Track and monitor all access to network resources and cardholder data
  2. Test security systems and processes regularly

📖 Maintain an Information Security Policy

  1. Maintain a policy that addresses information security for all personnel

⚙️ How to Implement PCI DSS Compliance

✅ 1. Determine Your PCI Level

  • PCI compliance is based on your annual transaction volume.
  • Level 1 (over 6 million transactions/year) requires a formal audit by a Qualified Security Assessor (QSA).

✅ 2. Scope Your Environment

  • Identify systems and processes that handle CHD
  • Limit scope by network segmentation

✅ 3. Implement Required Controls

  • Firewalls, encryption (TLS 1.2+), anti-malware, logging, intrusion detection
  • Strong authentication (e.g. MFA for admins)

✅ 4. Complete a Self-Assessment Questionnaire (SAQ)

  • For merchants that don’t require full audits
  • Several SAQ types depending on how payments are handled (e.g. e-commerce, POS, hosted forms)

✅ 5. Conduct Vulnerability Scanning

  • Quarterly ASV scans from an Approved Scanning Vendor
  • Remediate vulnerabilities and retain reports

✅ 6. Maintain Logs and Monitoring

  • Centralised logging (e.g. Splunk)
  • Retain logs for at least one year

✅ 7. Train Staff

  • Educate teams on handling cardholder data securely
  • Include phishing awareness and secure coding practices

🧰 Tools That Support PCI DSS Compliance

  • Wazuh / Splunk – Logging, alerting, and file integrity monitoring
  • AWS Config / Azure Policy – Enforce secure configurations in cloud
  • Tenable / Qualys – Vulnerability management
  • HashiCorp Vault / AWS KMS – Encryption key management
  • CrowdStrike / SentinelOne – Endpoint protection

🚨 Non-Compliance Consequences

Failure to comply can result in:

  • Hefty fines ($5,000 to $100,000/month)
  • Termination of merchant accounts
  • Mandatory forensic audits
  • Damage to brand trust and customer confidence

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