TMA-MSSQL-7.2
Ensure Asymmetric Key Size is set to 'greater than or equal to 2048' in non-system databases
MediumLevel 1Automatedmssql
Description
Microsoft Best Practices recommend to use at least a 2048-bit encryption algorithm for asymmetric keys. Iterates user databases (database_id > 4). Default: None 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
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 database_id > 4; 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 name FROM sys.asymmetric_keys WHERE key_length < 2048) 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
Refer to Microsoft SQL Server Books Online ALTER ASYMMETRIC KEY entry: https://docs.microsoft.com/en-us/sql/t-sql/statements/alter-asymmetric-key-transact-sql
Properties
- Operating systems
- Any
- Tags
- mssqldatabaseencryption
- Reference
- CIS Microsoft SQL Server 2025 Benchmark v1.0.0 - 7.2 Ensure Asymmetric Key Size is set to 'greater than or equal to 2048' in non-system databases
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
shell
tmaegis scan --target mssql