Yes. This threat is real. Corebot is a Banker Trojan used in an attempt to obtain confidential information about online banking and payment systems. There is a decent write up about Trojan: Win32/Corebot here
If any of your computers were used for online banking, has credit card information or other sensitive data on it, you should NOT
reconnect any of them to the Internet until your systems are clean or have been reformatted.ALL
passwords should be changed immediately
, even if you choose to reformat, to include those used for banking, email, eBay, paypal and online forums. You should consider them to be compromised. You should change each password by using a CLEAN COMPUTER
and not the infected ones. If not, an attacker may get the new passwords and transaction information. If using a router, you will need to reset it with a strong logon/password so the malware cannot gain control before connecting again. Banking and credit card institutions should be notified as soon as possible due to the possibility of the security breach.
Though the trojan has been identified and can possibly be cleansed, because of it's backdoor functionality, your PC is very likely compromised and there is no way to be sure your computer can ever again be trusted. Many experts in the security community believe that once infected with this type of trojan, the best course of action would be a reformat and reinstall of the OS.
Because your computer was compromised please read the following links:How Do I Handle Possible Identify Theft, Internet Fraud and CC Fraud?When should I re-format? How should I reinstall?Let me know if you would like to proceed with trying to disinfect your computer(s). If so, I would prefer to start with your Windows 7 computer.
In order to see what we are dealing with, we will need to see some logs and since it is best to not connect the computer(s) to the internet we will need access to a known clean computer and a known clean USB drive to transfer files from and to the infected computer.