The Ubuntu operating system must prohibit password reuse for a minimum of five generations.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-238234 | UBTU-20-010070 | SV-238234r1015152_rule | CCI-000196 | low |
| Description | ||||
| Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. If the information system or application allows the user to consecutively reuse their password when that password has exceeded its defined lifetime, the end result is a password that is not changed as per policy requirements. Satisfies: SRG-OS-000077-GPOS-00045, SRG-OS-000073-GPOS-00041 | ||||
| STIG | Date | |||
| Canonical Ubuntu 20.04 LTS Security Technical Implementation Guide | 2025-05-16 | |||
Details
Check Text (C-238234r1015152_chk)
Verify the Ubuntu operating system prevents passwords from being reused for a minimum of five generations by running the following command:
$ grep -i remember /etc/pam.d/common-password
password [success=1 default=ignore] pam_unix.so obscure sha512 shadow remember=5 rounds=5000
If the "remember" parameter value is not greater than or equal to "5", is commented out, or is not set at all, this is a finding.
Fix Text (F-41403r832944_fix)
Configure the Ubuntu operating system to prevent passwords from being reused for a minimum of five generations.
Add or modify the "remember" parameter value to the following line in "/etc/pam.d/common-password" file:
password [success=1 default=ignore] pam_unix.so obscure sha512 shadow remember=5 rounds=5000