30.10.15

Trick or treat? Watch out so a ransomware won’t end up between your Halloween sweets


By Ondrej Kubovič

There are many spooky things in this world and Halloween brings them all to the spotlight. Does your biggest fear involve spiders, zombies, ghosts, horror movies or is it rather something from cyberspace? Many online users would probably opt for the latter – after their experience with ransomware.


It’s due to the methods this kind of malware uses when attacking its victims. Honestly, who wouldn’t get spooked by computer screen suddenly flashing a notice from your local police that your computer contains illegal data, subjecting you to hundreds of dollars in fine? Ok, this could be a bit too obvious…

Or take another way of making its victims squirm often used by the cybercriminals regardless if it’s Halloween, European Cyber Security Month, or Mother Theresa Day. It involves placing a giant countdown timer smack in the middle of your screen. And if you don’t comply within the given timeframe, you risk losing access to all the valuable data, which is now encrypted by the malware.
And flaming fears is exactly what the cybercriminals want. They don’t need a mask or dramatic music to scare the hell out of their victims. They simply force them to act under pressure, inviting mistakes along the way. Their one aim is to extort money − and in the worst case scenario, not even bother returning/decrypting the captured information.

Boogeymen for your mobile devices
And you want to know what is really annoying about ransomware?  The bad guys are moving over from PCs and laptops to mobile platform, making their malware creations even more sophisticated along the way. So, the bad news is, you need to be a bit more careful on your mobile. Here is why:
Android/Lockerpin.A discovered by ESET only a few weeks ago. It is a first mobile lock-screen-type ransomware detected by ESET research that sets the phone’s PIN lock. After this, the victims are forced to pay $500 for the alleged viewing and harboring of forbidden pornographic material. Spooky, isn’t it?

In 2014 there was another nasty piece of malware at work – dubbed Simplocker. Its goal? Scanning the SD card of the infected Android smartphone, looking for specific extensions, and encrypting the files until the ransom is paid for their decryption.
But as we mentioned earlier, aggressive ransomware isn’t just targeting mobile platforms.  At the beginning of 2015, CTB-Locker (detected by ESET Telemetry as Win32/Filecoder.DA) was spotted making its rounds on desktops and laptops.

It spread through fake emails purporting to contain an important fax message (Yes, fax oddly enough). The actual attachment was a downloader (detected by ESET as Win32/TrojanDownloader.Elenoocka.A) intended to download a variant of Filecoder. This all under time pressure heightened by a countdown function.

Again, the CTB-Locker’s ultimate goal was to encrypt files on the victim’s device and extort them for bitcoins – as a means of staying anonymous. It even contained instructions for obtaining this cryptocurrency, in case the user had none in their stash. To enhance its reach, the extortion message was translated to four languages – German, Dutch, Italian, and English – also adjusting the currency to the specific region.

So what’s the trick for staying safe?
Of course this article does not have the ambition to offer an exhaustive list of all the ransomware out there (or malware in general). There are others that would “deserve” to be mentioned – from recent Cryptolocker, Torrentlocker or CryptoFortress, all the way back to the first ransomware PC Cyborg – but the more pressing question is: how to shield yourself from these threats?


There are actually lists of advice put together by ESET researchers over the years, offering guidance not only for the cases of ransomware infections, but for many other types of malware. To save you time, what it basically boils down to is prevention. Keeping your systems backed-up, updated and using a reliable security solution are the very first steps, which help you to keep online boogeymen away from your doorstep and chase away your worst cyber nightmares.