PCI DSS 8.3.2: Encrypt Authentication Credentials in Transmission and Storage

What this means

Strong cryptography means using industry-standard encryption algorithms (like AES-256 or TLS 1.2+) to protect passwords, API keys, tokens, and other authentication materials both when they travel across networks and when stored in databases or configuration files. Plaintext credentials—whether in logs, backups, or memory—violate this requirement. The goal is to ensure that even if an attacker intercepts or accesses stored data, credentials remain unreadable without the encryption key.

How to comply

1. 1.Identify all locations where authentication credentials are stored (databases, configuration files, backup systems, memory) and transmitted (network connections, APIs, third-party integrations)
2. 2.Implement TLS 1.2 or higher for all credential transmission over networks; avoid HTTP or unencrypted protocols
3. 3.Apply strong encryption (AES-256 or equivalent) to credentials stored in databases, files, and backups using dedicated key management systems
4. 4.Use industry-standard hashing algorithms (bcrypt, scrypt, or PBKDF2) for password storage; never store plaintext passwords
5. 5.Manage encryption keys securely using a key management service (KMS) or hardware security module (HSM); rotate keys regularly
6. 6.Remove or mask credentials from logs, error messages, and debugging output to prevent accidental exposure
7. 7.Audit and monitor access to encrypted credentials; maintain logs of who accessed what and when
8. 8.Test encryption implementation through vulnerability scans and penetration testing to verify credentials cannot be recovered

Evidence auditors look for

• TLS/SSL certificates configured for all credential transmission endpoints with TLS 1.2 minimum version enforced
• Database encryption enabled with AES-256 for all authentication credential columns
• Credential management vaults (e.g., HashiCorp Vault, AWS Secrets Manager) configured with encryption at rest and in transit
• Hashed passwords verified in production databases (no plaintext passwords found in audits)
• Key rotation policy documentation showing encryption keys rotated at defined intervals
• Log sanitization rules configured to redact credentials from application and system logs
• Access control logs showing only authorized personnel can retrieve or decrypt credentials
• Penetration test reports confirming credentials cannot be extracted from transmission or storage

Frequently asked questions

GRCWatch automates credential encryption validation by scanning your infrastructure to identify unencrypted credentials in transit and storage, flagging violations, and tracking remediation—reducing manual audit effort and PCI DSS 8.3.2 assessment risk.

See how GRCWatch handles this control automatically

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