The Cisco VPN remote access server must be configured to use AES256 or greater encryption for the Internet Key Exchange (IKE) Phase 1 to protect confidentiality of remote access sessions.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-239979 | CASA-VN-000640 | SV-239979r987747_rule | CCI-000068 | high |
| Description | ||||
| Without confidentiality protection mechanisms, unauthorized individuals may gain access to sensitive information via a remote access session. Remote access is access to DOD nonpublic information systems by an authorized user (or an information system) communicating through an external, non-organization-controlled network. AES is the FIPS-validated cipher block cryptographic algorithm approved for use in DOD. For an algorithm implementation to be listed on a FIPS 140-2/140-3 cryptographic module validation certificate as an approved security function, the algorithm implementation must meet all the requirements of FIPS 140-2/140-3 and must successfully complete the cryptographic algorithm validation process. Currently, NIST has approved the following confidentiality modes to be used with approved block ciphers in a series of special publications: ECB, CBC, OFB, CFB, CTR, XTS-AES, FF1, FF3, CCM, GCM, KW, KWP, and TKW. | ||||
| STIG | Date | |||
| Cisco ASA VPN Security Technical Implementation Guide | 2024-08-22 | |||
Related Frameworks
3 paths across 3 frameworks
Related Frameworks
NIST 800-531 mapping
AC-17(2)
1.00
- DISA · V2R2 · disa_xccdf · related
- DISA · 2025-01-23 · disa_cci_list · equivalent
NIST 800-1711 mapping
3.1.13
1.00
- DISA · V2R2 · disa_xccdf · related
- DISA · 2025-01-23 · disa_cci_list · equivalent
- NIST · Rev 2 (Feb 2020, errata Jan 2021) · nist_800_171_app_d · equivalent
CCI1 mapping
CCI-000068
1.00
- DISA · V2R2 · disa_xccdf · related
Details
Check Text (C-239979r987747_chk)
Verify IKE Phase 1 is set to use an AES256 or greater encryption algorithm as shown in the example below.
crypto ipsec ikev2 ipsec-proposal IPSEC_TRANS
protocol esp encryption aes-256
If the value of the encryption algorithm for IKE Phase 1 is not set to use an AES256 or greater algorithm, this is a finding.
Fix Text (F-43171r916139_fix)
Configure the ASA to use AES256 or greater encryption algorithm for IKE Phase 1 as shown in the example below.
ASA1(config)# crypto ikev2 policy 1
ASA1(config-ikev2-policy)# encryption aes-256