Cybercriminals have turned to cryptocurrency mining malware as an easy, low-risk way of making money although ransomware is still the main malware threat according to Europol.
While it was common for large-scale spam email campaigns to be sent to random recipients to spread ransomware, tactics used to infect devices with the file-encrypting malware are changing.
There has been a decline in the use of ‘spray and pray’ spam campaigns involving millions of messages toward targeted attacks on businesses. Organized cybercriminal gangs are researching victims and are conducting highly targeted attacks that first involve compromising a network before manually deploying ransomware.
The cybercriminal group behind SamSam ransomware has been particularly prolific. Companies that have failed to address software vulnerabilities are attacked and access is gained to their networks. The SamSam group also conducts brute force attacks on RDP to gain access to business networks. Once access is gained, ransomware is manually installed on as many computers as possible, before the encryption routine is started across all infected devices. With a large number of devices encrypted, the ransom demand can be much higher – Typically around $50,000 per company. The group has collected at least $6 million in ransom payments to date.
Europol warns that ransomware attacks will continue to be a major threat over the following years, although a new threat is emerging – cryptojacking malware. This form of malware is used to hijack computer processors to mine cryptocurrency. Europol warns that if the rise in the use of cryptojacking malware continues it may overtake ransomware and become the biggest malware threat.
Not only does cryptojacking offer considerable rewards, in many cases use of the malware is not classed as illegal, such as when it is installed on websites. This not only means that cybercriminals can generate considerable profits, but the risk involved in these types of attacks is far lower than using ransomware.
Cybercriminals are still extensively using social engineering techniques to fool consumers and employees into disclosing sensitive personal information and login credentials. Social engineering is also extensively used to trick employees into making fraudulent bank transfers. Phishing is the most common form of social engineering, although vishing – voice phishing – and smishing – SMS phishing are also used. Europol notes that social engineering is still the engine of many cybercrimes.
While exploit kits have been extensively used to silently download malware, Europol notes that the use of exploit kits continues to decline. The main attack vectors are spam email and RDP brute-forcing.
As-a-service cyberattacks continue to be a major problem. DDoS-as-a-service and ransomware-as-a-service allow low-level and relatively unskilled individuals to conduct cyberattacks. Europol recommends law enforcement should concentrate on locating and shutting down these criminal operations to make it much harder for low-level criminals to conduct cyberattacks that would otherwise be beyond their skill level.
With spam email still a major attack vector, it is essential for businesses to implement cybersecurity solutions to prevent malicious emails from being delivered to inboxes and ensure cybersecurity best practices are adopted to make them less susceptible to attack. With phishing the main form of social engineering, anti-phishing training for employees is vital.
RDP attacks are now commonplace, so steps must be taken by businesses to block this attack vector, such as disabling RDP if it is not required, using extremely strong passwords for RDP, limiting users who can login, configuring account lockouts after a set number of failed login attempts, and using RDP gateways.