As noted in the previous two posts, there was a virus outbreak on server NC036 (the primary mail server) this morning. Apparently the machines associated with five email accounts on three domains were compromised, allowing criminals to use those accounts to send thousands of viruses. These were intercepted by our anti-virus scanner, but due to the volume of activity on the server we had to shut down the SMTP side of the mail server while we determined which email accounts were compromised, suspended them and removed their messages from the mail queue.
Please note that what happens in almost all cases when email accounts are compromised is that the computer (or one of the machines or devices on which those accounts are configured) is what is actually compromised; it is not the server. The account owner’s machine is usually infected with a virus or other malware, and the account’s password is then transmitted to the criminals behind the virus. They then launch an attack via the legitimate and correct password. It’s as if your car was stolen and the thief used it to commit a crime; the car behaved as it was told by the guy with the key, but is not responsible for the crime. On the other hand, the owner of the car may have left the key in their car and the door unlocked, contributing to the compromise. This is why it is vitally important that you have anti-virus software installed on your computer, and kept up-to-date.
If you have any questions about this, please feel free to contact NinerNet support, and we’ll be happy to answer your questions or concerns. Our apologies for the interruption.