Title

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

Discussion

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.

Check Content

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.

Fix Text

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

Additional Identifiers

Rule ID: SV-239958r916134_rule

Vulnerability ID: V-239958

Group Title: SRG-NET-000168-VPN-000600

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.