Got a great business idea? Want to expand with less risk? Build a good product, develop some training, put them together into a repeatable formula, and collect the royalties from your franchisees. This model, used successfully for everything from fast food to hair salons to tax preparation, is now available for criminal ransomware.
Cybercriminals have long been making their tools available to others, whether due to pride of authorship or as a means of raking in some extra cash. However, the ransomware-as-a-service model is relatively new and has resulted in a massive increase in ransomware attacks (as reported in the latest quarterly Threats Report). CTB-Locker and Tox are two examples of how malware uses different business models to flood the Internet with attacks, trying to catch more victims before threat notices, signature updates, and other defensive measures catch up.
Since the servers for CryptoLocker were taken down last year, CTB-Locker has become one of the most common sources of ransomware attacks. CTB-Locker uses an affiliate program to drive growth and revenue. Criminals who sign up as an affiliate get the tools to distribute this ransomware to their own selection of targets and collect 70% of the resulting revenue. Distribution vectors are typically phishing emails such as delivery notifications and fake software updates. Once your files are encrypted, you are left with .bmp, .txt, and .html files that contain information on how to pay the ransom to get your files back. Removing the malware is relatively easy. However, decrypting the files, which are encrypted with RSA 2,048-bit private-key encryption, is close to impossible. Payment is expected in Bitcoin, which preserves the criminal’s anonymity.
Malware For Hire
Tox is another ransomware that is growing in popularity. The authors of Tox offer a ransomware kit that requires very little in the way of technical skills. Simply provide the ransom amount and “cause” for which you are fundraising, and you get your own executable file. Install or distribute as you see fit for a mere 20% of your gross ransoms, also payable in Bitcoin. Both Tox and CTB-Locker use the TOR network to get their encryption keys and hide the IP addresses of their servers to avoid the fate of CryptoLocker and evade endpoint security systems.
Bitcoin and other virtual currencies are an important part of ransomware. By protecting anonymity, data kidnappers can go after more lucrative targets, which might otherwise have the ability to track down the perpetrators. As a result, these attacks are shifting from consumer systems to business systems, in the hopes of getting more and bigger ransoms. Many organizations appear to be paying ransoms to get their data back, validating the model and fueling further attacks.
Ransomware has evolved and is spreading quickly, but it can be stopped. Frequent backups and user awareness remain the best protection against ransomware, followed by multipoint defenses. Anti-spam systems will catch many of the phishing emails, especially if they are configured to detect and block compressed files and executables. Consider blocking TOR network connections to prevent the ransomware from getting the encryption keys. Finally, keep system patches up to date and advanced security features configured and enabled on the endpoints.