The Soviets used to send SSNs to SSBN deployment areas. Not really an escort as you would call it since there is no formation but the intention was clearly protecting SSBNs. Sometimes they were pre-positioned on the route the SSBN will use to detect trackers.
If a Soviet SSN found something in the patrol area, how can they know it’s not their own SSBN?
One way that I can guess is that they would know the acoustic signature of their own ships, so anything not their own is a hostile. They just won't know what hostile in particular it was unless they had previous acoustic signatures stored.
