STIGUI
V-270726CAT II — Medium severitySV-270726r1066667_rule

Ubuntu 24.04 LTS must enforce password complexity by requiring that at least one uppercase character be used.

Rule version UBTU-24-400260 · STIG v1 · 2026-09-09

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.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.

Satisfies: SRG-OS-000069-GPOS-00037, SRG-OS-000730-GPOS-00190

Check

Verify Ubuntu 24.04 LTS enforces password complexity by requiring that at least one uppercase character be used with the following command:

$ grep -i "ucredit" /etc/security/pwquality.conf ucredit=-1

If the "ucredit" parameter is greater than "-1", is commented out, or is missing, this is a finding.

Fix

Configure Ubuntu 24.04 LTS to enforce password complexity by requiring that at least one uppercase character be used.

Add or update the "/etc/security/pwquality.conf" file to contain the "ucredit" parameter:

ucredit=-1

Identifiers

Group ID
V-270726
Group title
SRG-OS-000069-GPOS-00037
Rule ID
SV-270726r1066667_rule
Check ID
C-74759r1066665_chk
Fix ID
F-74660r1066666_fix