FIPS 140-2/140-3 precludes the use of invalidated cryptography for the cryptographic protection of sensitive or valuable data within federal systems. Unvalidated cryptography is viewed by NIST as providing no protection to the information or data. In effect, the data would be considered unprotected plaintext. If the agency specifies that the information or data be cryptographically protected, then FIPS 140-2/140-3 is applicable. In essence, if cryptography is required, it must be validated. Cryptographic modules that have been approved for classified use may be used in lieu of modules that have been validated against the FIPS 140-2/140-3 standard.
The cryptographic module used must have at least one validated digital signature function. This validated hash algorithm must be used to generate digital signatures for all cryptographic security function within the product being evaluated.
Check
Verify the API must use a FIPS-validated cryptographic module to provision digital signatures for tokens.
Authentication to microservices: APIs that have access to sensitive data must not be done simply by using API keys. Access to such APIs must require authentication tokens that have either been digitally signed (e.g., client credentials grant) or verified with an authoritative source.
Services may require either single-use tokens or short-lived tokens (tokens that expire after a short time period) to limit the damage a compromised token can cause.
If the API does not use a FIPS validated cryptographic module to provision signatures for tokens, this is a finding.
Fix
Build or configure the API to utilize a FIPS-validated cryptographic module to provision digital signatures.