ansomware targets businesses, government institutions, public services such as hospitals, council offices and of course people at home. Home computers are perhaps the easiest way for cyber-criminals to carry out attacks as your average Joe doesn't have a cyber-security department protecting him like businesses and organisations do. Many individuals at home think that an anti virus programme will protect them. This is simply not the case. As we have mentioned in previous blog posts, cyber-criminals sometimes distribute malware via online ads and landing pages, so if you are an ad network or a publisher, we recommend that you protect your users with a product such as AdSecure. Not only will you be helping to keep ransomware at bay, you will also be protecting users from being exposed to ransomware and keep that valuable trust from clients and website visitors because they will be protected from attack.
So let's have a closer look at the history of ransomware, why ransomware creators and distributors find home users easy targets and what happens when a user is infected.
The very first ransomware emerged way back in 1989. Named the AIDS Trojan, it spread via floppy disks and each victim was asked to send $189 ransom to a post office box in Panama. Of course nowadays ransomware is much more sophisticated and the growth of crypto-currencies has ensured ransomware is a much more attractive proposition to cyber criminals.
Types of ransomware
There are two types of ransomware: Locker ransomware, this locks the victim out of the operating system, which makes it impossible for them to access their desktop, apps and files. In this case the files are not encrypted, but the attackers ask for a ransom to unlock the infected computer. The second is Encrypting ransomware, which uses advanced encryption algorithms. It blocks system files and then demands payment in exchange for a key that can decrypt the blocked content.
Home users are easy targets and here's why…
- They rarely create, or don't do data backups.
- They don't always keep their software up to date.
- They think that it can't happen to them.
- They have little or no cyber security awareness/education, meaning that they can easily be persuaded to click on almost anything.
- They are much less likely to purchase cyber security solutions with most home users still relying on antivirus software, but this can be ineffective because ransomware uses evasion techniques so it is undetected by traditional antivirus software.
- And of course the sheer volume of home internet users can allow cyber-criminals to build up huge scale in order to exploit potential victims
The infection – stage 1
What generally happens when a user unknowingly infects his computer from a malicious website or link that he clicks on? The infection delivers a security exploit to create a backdoor on the victim's computer using vulnerable software on their system. Once the victim has unwittingly clicked on a link or downloads and opens the attachment, a downloader (payload) will be placed on the affected PC. The downloader uses a list of domains or C&C servers controlled by cyber criminals to place the ransomware program on the system. The contacted C&C server responds by sending back the requested data. The infected PC can be turned into a botnet, so that the cyber criminals can grow their infrastructure and carry out future attacks, and it can spread to other PCs connected to a local network, which causes further damage.
The infection – stage 2
It then uses unbreakable encryption, which means a victim cannot decrypt the files using the various decryption tools available from cyber security researchers. It has the ability to encrypt many different kinds of files on a victim's PC including photos, videos, documents, audio files, etc. It encrypts data stored in cloud accounts such as Google Drive and Dropbox that are synced on the PC. It can also encrypt data on other computers connected to a local network. It scrambles file names, so the victim has no idea which data is affected. This is done in order to confuse and coerce victims into paying the ransom. It can also extract data from the infected PC such as usernames, passwords, email addresses, etc. which it then sends to the server controlled by the cyber criminals.
The infection – stage 3
It then displays an image/message that tells the victim that their data has been encrypted and that they have to pay to get their data back. It can also include geographical targeting, so that the ransom note is translated into the victim's language, increasing the chances for the ransom to be paid. Payment is usually requested in Bitcoins, because crypto-currency cannot be tracked by cyber security researchers or law enforcement agencies. Generally there is a set time period to pay and missing the deadline means the ransom will increase, but it can also mean that the data will be destroyed and lost forever.
As you can see this can be a shocking experience for your average Joe at home and with 638 million ransomware attacks in 2016, it is inevitable that the number of ransomware attacks will only increase.