The Ubuntu operating system must automatically lock an account until the locked account is released by an administrator when three unsuccessful logon attempts have been made.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-238235 | UBTU-20-010072 | SV-238235r958736_rule | Low |
| Description |
| By limiting the number of failed logon attempts, the risk of unauthorized system access via user password guessing, otherwise known as brute-forcing, is reduced. Limits are imposed by locking the account. Satisfies: SRG-OS-000329-GPOS-00128, SRG-OS-000021-GPOS-00005 |
| STIG | Date |
| Canonical Ubuntu 20.04 LTS Security Technical Implementation Guide | 2024-08-22 |
Details
| Check Text (C-41445r802381_chk) |
| Verify that the Ubuntu operating system utilizes the "pam_faillock" module with the following command: $ grep faillock /etc/pam.d/common-auth auth [default=die] pam_faillock.so authfail auth sufficient pam_faillock.so authsucc If the pam_faillock.so module is not present in the "/etc/pam.d/common-auth" file, this is a finding. Verify the pam_faillock module is configured to use the following options: $ sudo egrep 'silent|audit|deny|fail_interval| unlock_time' /etc/security/faillock.conf audit silent deny = 3 fail_interval = 900 unlock_time = 0 If the "silent" keyword is missing or commented out, this is a finding. If the "audit" keyword is missing or commented out, this is a finding. If the "deny" keyword is missing, commented out, or set to a value greater than 3, this is a finding. If the "fail_interval" keyword is missing, commented out, or set to a value greater than 900, this is a finding. If the "unlock_time" keyword is missing, commented out, or not set to 0, this is a finding. |
| Fix Text (F-41404r802382_fix) |
| Configure the Ubuntu operating system to utilize the "pam_faillock" module. Edit the /etc/pam.d/common-auth file. Add the following lines below the "auth" definition for pam_unix.so: auth [default=die] pam_faillock.so authfail auth sufficient pam_faillock.so authsucc Configure the "pam_faillock" module to use the following options: Edit the /etc/security/faillock.conf file and add/update the following keywords and values: audit silent deny = 3 fail_interval = 900 unlock_time = 0 |