The Cisco ASA must be configured to use FIPS-validated SHA-2 at 384 bits or higher for Internet Key Exchange (IKE) Phase 1.

Without cryptographic integrity protections, information can be altered by unauthorized users without detection.

Although allowed by SP800-131Ar2 for some applications, SHA-1 is considered a compromised hashing standard and is being phased out of use by industry and government standards. Unless required for legacy use, DOD systems should not be configured to use SHA-2 for integrity of remote access sessions.

Review the ASA configuration to verify that SHA-2 at 384 bits or higher is specified for IKE Phase 1 as shown in the example below.

crypto ikev2 policy 1 … integrity sha384

If the ASA is not configured to use SHA-2 at 384 bits or higher for IKE Phase 1, this is a finding.

Configure the ASA to use FIPS-validated SHA-2 at 384 bits or higher for IKE Phase 1 as shown in the example below.

ASA2(config)# crypto ikev2 policy 1 ASA2(config-ikev2-policy)# integrity sha384