How to recover an overwritten SQL Server database We have SQL Server Standard Edition with several databases. We backup via a Windows Task that executes the sp_BackupDatabases procedure.

We have a case where a database got replaced by a backup from 2 days ago by mistake. 

Unfortunately the connection to the NAS crashed, so the last 4 days, there where no backups made.

Since a backup was restored over the current database, there is no transaction log we could use to manually undo the changes.

Does anyone have an idea how I can get a version of the database before the database was restored? For example, does sp_BackupDatabases  make a local temp backup and moves it then, so that this temp backup could be still available?
As far as SQL native backups are concerned, you can only restore to the last good backup that you have which is 4 days ago.  So, unfortunately, from a SQL server backup perspective you may have lost 4 days worth of data.

That being said, if this is a VM (HyperV, VMWare, etc) and there are snapshots, you may be in luck and your systems guys may be able to get the information back.