The Cisco ASA remote access VPN server must be configured to generate unique session identifiers using a FIPS-validated Random Number Generator (RNG) based on the Deterministic Random Bit Generators (DRBG) algorithm.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-239977 | CASA-VN-000610 | SV-239977r666337_rule | CCI-001188 | medium |
| Description | ||||
| Both IPsec and TLS gateways use the RNG to strengthen the security of the protocols. Using a weak RNG will weaken the protocol and make it more vulnerable. Use of a FIPS validated RNG that is not DRGB mitigates to a CAT III. | ||||
| STIG | Date | |||
| Cisco ASA VPN Security Technical Implementation Guide | 2024-08-22 | |||
Details
Check Text (C-239977r666337_chk)
Review the ASA configuration to verify that FIPS mode has been enabled as shown in the example below.
ASA Version x.x
!
hostname ASA1
fips enable
If the ASA is not configured to be enabled in FIPS mode, this is a finding.
Fix Text (F-43169r666336_fix)
Configure the ASA to have FIPS-mode enabled as shown in the example below.
ASA1(config)# fips enable
ASA1(config)# end
Note: FIPS mode change will not take effect until the configuration is saved and the device rebooted.