Well, if you haven't noticed already, some to most of the internet is down! This is due to an exploit in Microsoft SQL Server SP2 and lower.
A buffer overrun can allow hackers to run code on the SQL Server. This worm, infects an SQL Server and then that SQL Server infects others.
My reccomendation? APPLY SP3!
If you have been infected, these steps should be taken:
1. Stop and DISABLE the MSSql Service, and all related ones
2. Stop and DISABLE IIS (if running)
3. Apply the SP3 Support Pack
5. Start and ENABLE the core MSSql Server (Not the Transaction Coordinator, etc)
6. Change your SA password!
7. Start and ENABLE all other stopped services.