Title

Windows Server 2016 built-in guest account must be renamed. (Cat II impact)

Discussion

The built-in guest account is a well-known user account on all Windows systems and, as initially installed, does not require a password. This can allow access to system resources by unauthorized users. Renaming this account to an unidentified name improves the protection of this account and the system.

Check Content

Verify the effective setting in Local Group Policy Editor. Run "gpedit.msc". Navigate to Local Computer Policy >> Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options. If the value for "Accounts: Rename guest account" is not set to a value other than "Guest", this is a finding. For server core installations, run the following command: Secedit /Export /Areas SecurityPolicy /CFG C:\Path\FileName.Txt If "NewGuestName" is not something other than "Guest" in the file, this is a finding.

Fix Text

Configure the policy value for Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> "Accounts: Rename guest account" to a name other than "Guest".

Additional Identifiers

Rule ID: SV-225027r991589_rule

Vulnerability ID: V-225027

Group Title: SRG-OS-000480-GPOS-00227

Expert Comments

CCIs tied to check.

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