The Cisco router must be configured to use FIPS-validated Keyed-Hash Message Authentication Code (HMAC) to protect the integrity of remote maintenance sessions.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-215699	CISC-ND-001200	SV-215699r808537_rule		High

Description
Unapproved mechanisms that are used for authentication to the cryptographic module are not verified and therefore cannot be relied upon to provide confidentiality or integrity, and DoD data may be compromised. Nonlocal maintenance and diagnostic activities are those activities conducted by individuals communicating through a network, either an external network (e.g., the Internet) or an internal network. Currently, HMAC is the only FIPS-approved algorithm for generating and verifying message/data authentication codes in accordance with FIPS 198-1. Products that are FIPS 140-2 validated will have an HMAC that meets specification; however, the option must be configured for use as the only message authentication code used for authentication to cryptographic modules.

Description

Unapproved mechanisms that are used for authentication to the cryptographic module are not verified and therefore cannot be relied upon to provide confidentiality or integrity, and DoD data may be compromised. Nonlocal maintenance and diagnostic activities are those activities conducted by individuals communicating through a network, either an external network (e.g., the Internet) or an internal network. Currently, HMAC is the only FIPS-approved algorithm for generating and verifying message/data authentication codes in accordance with FIPS 198-1. Products that are FIPS 140-2 validated will have an HMAC that meets specification; however, the option must be configured for use as the only message authentication code used for authentication to cryptographic modules.

STIG	Date
Cisco IOS Router NDM Security Technical Implementation Guide	2021-11-19

Details

Check Text ( C-16893r808535_chk )
Review the Cisco router configuration to verify that it is compliant with this requirement as shown in the example below. SSH Example ip ssh version 2 ip ssh server algorithm mac hmac-sha2-256 HTTPS Example ip http secure-server ip http secure-ciphersuite aes-128-cbc-sha ip http secure-client-auth ip http secure-trustpoint CA_XXX If the Cisco router is not configured to use FIPS-validated HMAC to protect the integrity of remote maintenance sessions, this is a finding.

Check Text ( C-16893r808535_chk )

Review the Cisco router configuration to verify that it is compliant with this requirement as shown in the example below.

SSH Example

ip ssh version 2
ip ssh server algorithm mac hmac-sha2-256

HTTPS Example

ip http secure-server
ip http secure-ciphersuite aes-128-cbc-sha
ip http secure-client-auth
ip http secure-trustpoint CA_XXX

If the Cisco router is not configured to use FIPS-validated HMAC to protect the integrity of remote maintenance sessions, this is a finding.

Fix Text (F-16891r808536_fix)
The Cisco router is not compliant with this requirement. However, the risk associated with this requirement can be fully mitigated if the router is configured. Configure SSH and HTTPs to use FIPS-validated HMAC for remote maintenance sessions as shown in the following examples: SSH Example R1(config)#ip ssh version 2 R1(config)#ip ssh server algorithm mac hmac-sha2-256 HTTPS Example R2(config)#ip http secure-ciphersuite aes-128-cbc-sha

Fix Text (F-16891r808536_fix)

The Cisco router is not compliant with this requirement. However, the risk associated with this requirement can be fully mitigated if the router is configured.

Configure SSH and HTTPs to use FIPS-validated HMAC for remote maintenance sessions as shown in the following examples:

SSH Example

R1(config)#ip ssh version 2
R1(config)#ip ssh server algorithm mac hmac-sha2-256

HTTPS Example

R2(config)#ip http secure-ciphersuite aes-128-cbc-sha