Malicious actors target victims through phishing attacks, exploiting vulnerabilities, and using ransomware-as-a-service. They encrypt files to render them inaccessible and demand payment for the decryption key.
Detecting ransomware often depends on malware signatures but can be challenging when attackers modify existing variants. Behavioral detection can be more effective, as it observes system behavior and flags unusual activity.
It Encrypts Files
Once ransomware has gained access to a system, it begins encrypting files. It does so by adding an extension that prevents the victim from accessing those files without a decryption key, which the attackers hold. It then displays a message to victims, explaining that their systems are inaccessible and that they will need to pay a fee to cybercriminals to gain access again.
Infections of this kind of malware typically occur when a victim opens a malicious attachment or clicks a link found in an email sent by criminals. However, attacks can also be caused by security vulnerabilities that haven’t been patched.
The best way to mitigate ransomware virus attacks is to keep data backups separate from the original files on the system. Additionally, it’s essential to ensure backup files aren’t easily accessible to attackers, such as by encrypting or deleting them. To further protect against ransomware, organizations should implement applications that allow listing and software restriction policies and keep devices’ operating systems and applications current. Also, network segmentation can limit attackers’ ability to move laterally within the system and access critical data or systems.
It Deletes Files
When crypto ransomware encrypts files, it locks users out of their data. This creates panic, as the victim knows they’ll lose vital information if they don’t pay in time. To add to the pressure, hackers often use a countdown timer and threaten to delete all the files on their system.
This attack is hazardous for healthcare and professional services companies, which face the highest risk of paying a ransom to retrieve their files. Attackers know that, unlike many other industries, they will likely be more willing to pay a small fee to get back their data quickly, as their livelihoods depend on it.
An excellent way to combat this threat is by creating secure, ongoing backups of all critical files to an external physical device. Ideally, these devices should be disconnected from the network to prevent infection. Also, if a computer uses more CPU or disk space than usual, shutting down regular programs and processes can ease the burden. If this doesn’t help, disconnecting the computer from Wi-Fi and wired networks can prevent the malware from spreading and contacting command-and-control servers.
It Blocks Access to Files
Victims typically receive a pop-up or email stating they cannot access their files until they pay the sum demanded. Payment is generally made through cryptocurrency like Bitcoin because it is nearly impossible to trace.
Ransomware can be prevented by patching operating systems, software, and applications and by implementing security measures that prevent the infection of devices and networks, such as application allow listing and Software Restriction Policies (SRP). Additionally, deploying network segmentation will make it more difficult for attackers to move laterally across an organization and access sensitive systems or data.
While most ransomware attacks are opportunistic and disseminated through indiscriminate infection vectors, there are rare instances when cyber threat actors target specific entities with strategically-encrypted variants of Reveton or other ransomware. These attacks are often referred to as “extortion” ransomware. This type of ransomware is beautiful to criminals because it requires the victim to make a decision that can cripple their business or personal life. For this reason, these attackers are more likely to target government agencies, medical facilities, and law firms.
It Demands Money
As with other extortion-type malware, ransomware attackers demand money in return for unlocking a victim’s system. This payment is usually made through wire transfers or cryptocurrencies such as Bitcoin.
Like other malware, ransomware can be detected by looking for known signatures of malicious files. However, these methods are less effective against new or modified ransomware variants. Instead, relying on behavioral detection that monitors system behavior for suspicious or abnormal activity is better.
In addition to the threat of having their data published online or otherwise leaked, victims can risk losing business or failing to meet regulatory requirements. Fortunately, backing up data in advance and using proper cybersecurity can significantly reduce the intensity of a ransomware attack.
Attackers choose the victims they target for a variety of reasons. For example, hospitals make tempting targets because attackers know that medical professionals may be more likely to pay a low ransom to avoid the disruption of patient care. Other high-profile targets include law firms with sensitive client data and meat processing companies that must keep their production lines running.
It Spreads
Ransomware is a specific type of malware that uses encryption to disrupt computers, files, servers, and networks. Hackers then extort organizations for substantial sums to restore access to their data or unencrypt files. The hackers often demand cryptocurrency payments because they offer some level of anonymity. Hackers can permanently block their systems or even release data to public shaming sites and dark markets if victims refuse to pay the demanded sums.
Ransomware usually spreads through phishing emails with malicious attachments or links but can also use remote desktop protocols (RDP), unsecured websites, and vulnerabilities in software. Once hackers gain access to a network, they can infect more machines using these methods.
Cyber threat actors target many organizations, including healthcare facilities and universities. Some organizations have the resources to pay large ransom amounts so that attackers can make significant profits. Cybercriminals may develop ransomware that targets critical infrastructures and paralyze entire ecosystems until payment is made. The threat of such an attack increases due to hackers stealing or sharing ransomware code.
