The Kerberos policy user ticket renewal maximum lifetime must be limited to seven days or less.

STIG ID: WN16-DC-000050  |  SRG: SRG-OS-000112-GPOS-00057 | Severity: medium |  CCI: CCI-001941,CCI-001942

Vulnerability 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.

Satisfies: SRG-OS-000112-GPOS-00057, SRG-OS-000113-GPOS-00058

Check

This applies to domain controllers. It is NA for other systems.

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

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 a maximum of "7" days or less.