Title

The Kerberos user ticket renewal maximum lifetime must be limited to 7 days or less. (Cat II impact)

Discussion

This setting determines the period of time (in days) during which a user's Ticket Granting Ticket (TGT) may be renewed. This security configuration limits the amount of time an attacker has to crack the TGT and gain access.

Check Content

Verify the following is configured in the Default Domain Policy. Open "Group Policy Management". Navigate to "Group Policy Objects" in the Domain being reviewed (Forest >> Domains >> Domain). Right click on the "Default Domain Policy", select "Edit". Navigate to Computer Configuration >> Policies >> Windows Settings >> Security Settings >> Account Policies >> Kerberos Policy. If the "Maximum lifetime for user ticket renewal" is greater than "7" days, this is a finding.

Fix Text

Configure the policy value in the Default Domain Policy for Computer Configuration >> Policies >> Windows Settings >> Security Settings >> Account Policies >> Kerberos Policy >> "Maximum lifetime for user ticket renewal" to "7" days or less.

Additional Identifiers

Rule ID: SV-28501r2_rule

Vulnerability ID: V-2379

Group Title: Kerberos-User Ticket Renewal

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.