SQLAT is a suite of tools which could be useful for pen-testing a MS SQL Server. The tools do dictionary attacks, upload files, read registry and dump the SAM. They do this by wrapping extended stored procedures. There is also a tool for doing a minimal analysis of a SQL Server with output as HTML. You need to be 'sa' to run some of the tools, but this usually isn't a problem. SQLAT works over port 1433.
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