TMA-MSSQL-3.2
Ensure CONNECT permissions on the 'guest' user is Revoked within all SQL Server databases
Description
Remove the right of the guest user to connect to SQL Server databases, except for master, msdb, tempdb, and, on AWS RDS instances, rdsadmin. Iterates all online user databases (master, tempdb and msdb excluded; on AWS RDS rdsadmin is also acceptable). Default: The guest user cannot have the CONNECT permission revoked in master, msdb, tempdb, and, on AWS RDS instances, rdsadmin; however, this permission should be revoked in all other databases on the ... Runs one sqlcmd query with its defaults (Windows authentication to the local default instance); set SQLCMDSERVER, SQLCMDUSER and SQLCMDPASSWORD for another instance or SQL authentication. Needs VIEW SERVER STATE / sysadmin-level read access.
How it is checked
Audit method: SQL query
sqlcmd -b -h -1 -W -Q "SET NOCOUNT ON; DECLARE @n int = 0, @k int, @db sysname, @s nvarchar(max); DECLARE c CURSOR LOCAL FAST_FORWARD FOR SELECT name FROM sys.databases WHERE state = 0 AND HAS_DBACCESS(name) = 1 AND name NOT IN ('master','tempdb','msdb'); OPEN c; FETCH NEXT FROM c INTO @db; WHILE @@FETCH_STATUS = 0 BEGIN SET @s = N'USE ' + QUOTENAME(@db) + N'; SELECT @k = COUNT(*) FROM (SELECT permission_name FROM sys.database_permissions WHERE grantee_principal_id = DATABASE_PRINCIPAL_ID(''guest'') AND state_desc LIKE ''GRANT%'' AND permission_name = ''CONNECT'') AS x;'; EXEC sp_executesql @s, N'@k int OUTPUT', @k = @k OUTPUT; SET @n = @n + @k; FETCH NEXT FROM c INTO @db; END; CLOSE c; DEALLOCATE c; SELECT @n;"- Expected output
0
How it is fixed
Fix method: Guidance or infrastructure patch
The following code snippet revokes CONNECT permissions from the guest user in a database. Replace <database_name> as appropriate: USE <database_name>; GO REVOKE CONNECT FROM guest;
Properties
- Operating systems
- Any
- Tags
- mssqldatabaseprivileges
- Reference
- CIS Microsoft SQL Server 2025 Benchmark v1.0.0 - 3.2 Ensure CONNECT permissions on the 'guest' user is Revoked within all SQL Server databases
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
tmaegis scan --target mssql