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PCI-DSSfintechcompliance

PCI-DSS v4.0 for fintech startups: 10 errors audits detect

Published on 2026-03-087 min readFlorian

PCI-DSS v4.0: stricter, broader

Version 4.0 strengthens requirements on authentication, encryption and monitoring.

The 10 frequent errors

  • No MFA on payment data admin access
  • Transaction logs containing card data in clear text
  • Payment API keys in versioned source code
  • No encryption of card data at rest
  • Transaction endpoints without rate limiting
  • Payment webhooks without signature verification
  • No network segmentation for card data environment
  • No quarterly documented vulnerability scan
  • Non-compliant password policy
  • No payment security incident response procedure

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    Sources

    Written by Florian
    Reviewed on 2026-03-08

    Editorial analysis based on official vendor, project, and regulator documentation.

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