CVE-2018-16857

It was found that the 'bad password observation window' was ineffective when set to a value greater than 3 minutes. This could allow for brute force password attacks in some situations.

This flaw does not affect the version of samba shipped with Red Hat Enterprise Linux because there is no support for samba as Active Directory Domain Controller.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Bad password lockout is not configured by default, it is only effective if a threshold has been set with (eg):

samba-tool domain passwordsettings set --account-lockout-threshold=3

To mitigate the issue set a shorter 'Reset account lockout after' window (the ineffective default is 30, anything less than 15 will work):

samba-tool domain passwordsettings set --reset-account-lockout-after=15

NOTE: If a fine-grained password policy (PSO) is set, this must also be done on each PSO.