The Ubuntu operating system must require the change of at least 8 characters when passwords are changed.

From Canonical Ubuntu 16.04 LTS Security Technical Implementation Guide

Part of SRG-OS-000072-GPOS-00040

Associated with: CCI-000195

SV-90137r2_rule The Ubuntu operating system must require the change of at least 8 characters when passwords are changed.

Vulnerability discussion

If the Ubuntu operating system allows the user to consecutively reuse extensive portions of passwords, this increases the chances of password compromise by increasing the window of opportunity for attempts at guessing and brute-force attacks.The number of changed characters refers to the number of changes required with respect to the total number of positions in the current password. In other words, characters may be the same within the two passwords; however, the positions of the like characters must be different.If the password length is an odd number then number of changed characters must be rounded up. For example, a password length of 15 characters must require the change of at least 8 characters.

Check content

Verify the Ubuntu operating system requires the change of at least "8" characters when passwords are changed. Determine if the field "difok" is set in the "/etc/security/pwquality.conf" file with the following command: # grep -i "difok" /etc/security/pwquality.conf difok=8 If the "difok" parameter is less than "8", or is commented out, this is a finding.

Fix text

Configure the Ubuntu operating system to require the change of at least "8" characters when passwords are changed. Add or update the following line in the "/etc/security/pwquality.conf" file to include the "difok=8" parameter: difok=8

Pro Tips

Lavender hyperlinks in small type off to the right (of CSS class id, if you view the page source) point to globally unique URIs for each document and item. Copy the link location and paste anywhere you need to talk unambiguously about these things.

You can obtain data about documents and items in other formats. Simply provide an HTTP header Accept: text/turtle or Accept: application/rdf+xml.

Powered by sagemincer