Information
The operating system must be configured so that passwords are prohibited from reuse for a minimum of 5 generations.
Rationale:
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 per policy requirements.
Solution
To configure the operating system to prohibit password reuse for a minimum of 5 generations.
Add the following line in /etc/pam.d/system-auth and /etc/pam.d/password-auth (or modify the line to have the required value):
Example: vim /etc/pam.d/system-auth
Add, uncomment or update the following line:
password requisite pam_pwhistory.so use_authtok remember=5 retry=3
Note: Manual changes to the listed files may be overwritten by the authconfig program. The authconfig program should not be used to update the configurations listed in this requirement.
Notes:
This Benchmark recommendation maps to:
Red Hat Enterprise Linux 7 Security Technical Implementation Guide:
Version 2, Release: 3 Benchmark Date: 26 Apr 2019
Vul ID: V-71933
Rule ID: SV-86557r3_rule
STIG ID: RHEL-07-010270
Severity: CAT II