Since a couple of years it infects different computers, it damages lots of files making them unusable. It is a very dangerous ransomware, i.e. it asks for a ransom, and it’s called Cryptolocker. It affect computers with Windows and it spreads via email. The victim receive a message with an attachment but, if he opens it, the program ‘frees’ the virus. A lot of documents, of photos, and others, are encrypted with a specific key, which is different for every computer and it is saved in a server. It’s very difficult to find the key RSA-2048, the one used by Cryptolocker, because it would be necessary to use a high computer power and it would take some years. This is what frightens victims, who often think about paying for the key.
When the virus works, it opens a window on the screen, warning the owner. If he doesn’t pay, the key used for the encryption is deleted, so the files can’t be restored. Moreover, the timer will decrease if someone tries to remove Cryptolocker.
What to do?
It’s very important to know every working programs. For every email it’s necessary to verify the sender, to read the text and to distrust the attachments. The message with the virus often asks to download a document with some informations about refunds or similar. The danger is removed by deleting or ignoring these email.
If the infected document is opened, Cryptolocker could be stopped using an updated antivirus. But the virus is updated too, so it may pass the computer’s defence.
In any case, it’s better to not pay the ransom, because maybe the key won’t be delivered. The victim could, instead, load the backups saved before the virus, after of course having removed the virus. So it’s suggested to save backups once in a while to use them in case of emergency. In case are used systems like iCloud ir Dropbox, it’s important to disconnect the computer from the web as soon as Cryptolocker appears, so the infected datas wouldn’t be saved on the previous backup.
Unfortunately, if the files are encrypted and there isn’t a backup, it’s nearly impossible to restore them. Inquire about viruses, update antiviruses and verifing every email will delete every danger, in order to keep computers and datas safe.