Look at open ports
You can use the netstat tool built into Windows to see what ports are open and connected on the server. At a command prompt, simply enter netstat –an|more to get a page by page count of what TCP and UDP ports are open and listening. An even better way to go about doing this is to use Foundstone's Vision tool or Sysinternals' TCPView tool as shown below with the NetBus Trojan highlighted.
Sysinternals' TCPView maps open ports to actual executable files
This is another reason to know your SQL Server inside and out. If you know what you're looking at then you'll know what you're looking for.
Test for a Trojan horse on your SQL Server
Step 1: Scan your SQL Server for malware
Step 2: Look in the memory
Step 3: Look at open ports
Step 4: Peek into your network traffic
Step 5: Approach with a malicious mindset
ABOUT THE AUTHOR:
Kevin Beaver is an independent information security consultant and expert witness with Atlanta-based Principle Logic, LLC . He has more than 18 years of experience in IT and specializes in performing information security assessments revolving around compliance and IT governance. Kevin has authored/co-authored six books, including Hacking Wireless Networks For Dummies, and Securing the Mobile Enterprise For Dummies (all by Wiley), as well as The Practical Guide to HIPAA Privacy and Security Compliance (Auerbach).