The Cryptolocker virus that has been making it past some spam filters and destroying companies' files shares and file servers. Cryptolocker usually sneaks into your network by email attachment. The Cryptolocker virus is disguised in an email referencing a fax, delivery or shipment in the subject line. It is very important that if you get an email in with an attachment and you are not certain that you know who it is from, do not open it! Right click on the email and send it to junk mail, block the sender, and permanently delete the email by holding the shift key down and then right click to delete the message.
Cryptolocker goes straight to the hard drive and server and encrypts all files within your files shares including MS office files (excel, word, etc.) and also all pdfs. For the safety of your company data, please make sure that no employees open any emails or attachments that are questionable. Before you opening any attachments, be sure that you are 100% positive that you know who the email senders are.
Cryptolocker is a ransom-ware Trojan that is threatening computers running Microsoft Windows and first appeared in September 2013. When activated, the malware encrypts certain types of files stored on local and mounted network drives using RSA public key cryptography, with the private key stored only on the malware's control servers. The malware then displays a message which offers to decrypt the data if a payment is made by a given date, it also threatens to delete the private key if you exceed the given date. If the deadline is not met, the malware offers to decrypt data through an online service provided by the malware's operators, for a higher price in Bitcoin.
Although Cryptolocker itself is able to be removed, files remain encrypted in a way that researchers have considered to be very unlikely to crack. No instance of the files being unlocked after payment can be verified. Paying the ransom does not guarantee that you will get your data back. This is another reason is why having a proper backup solution is so important. For the safety of your network and data please take precautions when opening emails and attachments from unknown senders.