Ubuntu 24.04 LTS must implement smart card logins for multifactor authentication for local and network access to privileged and nonprivileged accounts over SSH.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-270722 | UBTU-24-400030 | SV-270722r1067130_rule | Medium |
| Description |
| Without the use of multifactor authentication, the ease of access to privileged functions is greatly increased. Multifactor authentication requires using two or more factors to achieve authentication. Factors include: 1) Something a user knows (e.g., password/PIN); 2) Something a user has (e.g., cryptographic identification device, token); and 3) Something a user is (e.g., biometric). A privileged account is defined as an information system account with authorizations of a privileged user. Network access is defined as access to an information system by a user (or a process acting on behalf of a user) communicating through a network (e.g., local area network, wide area network, or the internet). The DOD common access card (CAC) with DOD-approved PKI is an example of multifactor authentication. Satisfies: SRG-OS-000105-GPOS-00052, SRG-OS-000107-GPOS-00054, SRG-OS-000106-GPOS-00053, SRG-OS-000108-GPOS-00055 |
| STIG | Date |
| Canonical Ubuntu 24.04 LTS Security Technical Implementation Guide | 2025-05-16 |
Details
| Check Text (C-74755r1067129_chk) |
| Verify the sshd daemon allows public key authentication with the following command: $ sudo grep -r ^PubkeyAuthentication /etc/ssh/sshd_config* /etc/ssh/sshd_config:PubkeyAuthentication yes If "PubkeyAuthentication" is not set to "yes", is commented out, is missing, or conflicting results are returned, this is a finding. |
| Fix Text (F-74656r1066654_fix) |
| Configure Ubuntu 24.04 LTS to use multifactor authentication for access to accounts. Set the sshd option "PubkeyAuthentication" to "yes" in the "/etc/ssh/sshd_config" file. PubkeyAuthentication yes |