STIGUI
V-256501CAT II — Medium severitySV-256501r982198_rule

The Photon operating system must require that new passwords are at least four characters different from the old password.

Rule version PHTN-30-000024 · STIG v1 · 2026-08-31

Discussion

Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Check

At the command line, run the following command:

# grep pam_cracklib /etc/pam.d/system-password|grep --color=always "difok=."

Expected result:

password requisite pam_cracklib.so dcredit=-1 ucredit=-1 lcredit=-1 ocredit=-1 minlen=8 minclass=4 difok=4 retry=3 maxsequence=0 enforce_for_root

If the output does not include difok >= 4, this is a finding.

Fix

Navigate to and open:

/etc/pam.d/system-password

Add the following, replacing any existing "pam_cracklib.so" line:

password requisite pam_cracklib.so dcredit=-1 ucredit=-1 lcredit=-1 ocredit=-1 minlen=8 minclass=4 difok=4 retry=3 maxsequence=0 enforce_for_root

Note: On vCenter appliances, the equivalent file must be edited under "/etc/applmgmt/appliance", if one exists, for the changes to persist after a reboot.

Identifiers

Group ID
V-256501
Group title
SRG-OS-000072-GPOS-00040
Rule ID
SV-256501r982198_rule
Check ID
C-60176r887175_chk
Fix ID
F-60119r887176_fix