Top 7 Types of Ransomware Attacks

Ransomware attacks are becoming more common. They are usually spread through email attachments, malicious websites, infected USB drives, etc. Once installed, ransomware encrypts files on your computer, making them inaccessible unless you pay a ransom.

There are many different types of ransomware attacks. Some are designed to target specific operating systems (Windows, Mac OS X, etc.), and others are generic. Most are targeted at individuals, not businesses. Cryptowall targets Windows computers and demands USD 300 per machine, and CryptoDefense targets Mac OS X machines and USD 200 per machine.

What is a ransomware attack?

A ransomware attack occurs when someone gains access to your computer or mobile device by exploiting a vulnerability in your operating system or web browser. Once they gain control of your machine, they may install malware (malicious software) onto it, which will encrypt all your important files. They may then send you an email demanding money to unlock your files. If you don’t pay, they threaten to delete your files forever.

What are the different types of ransomware?

There are many different strains of ransomware out there. Some are designed to target specific industries, and others are designed to target individual users. Each strain will have its unique features, which means that it’s important to know what type of ransomware you’re dealing with before you start paying off the hacker.

Cryptoware – Cryptoware is a type of ransomware that locks down all of your files, and it can be used against both personal and commercial computers. There are several variations of cryptoware, and here are some examples:

CryptoLocker – This variant was first discovered in 2013. It uses AES 256-bit encryption to lock down your files. You have 72 hours to pay a ransom before permanently deleting your files.

TeslaCrypt – This variant was also discovered in 2013. It’s similar to CryptoLocker in terms of its encryption technology. However, unlike CryptoLocker, TeslaCrypt allows you to choose which files to encrypt.

Locky – This variant was discovered in 2014. It uses RSA 2048 bit encryption to lock down your data. Unlike other cryptowares, Locky doesn’t require a ransom payment to decrypt your files. Instead, it deletes encrypted files after seven days.

File Encryption – File encryption is ransomware where only specific files are locked down. These files include documents, images, videos, databases, spreadsheets, presentations, etc. This makes it easier to recover your files because you know exactly which ones were affected.

Here are some examples of file encryption:

WannaCry – This variant was discovered earlier this year. It affects Microsoft Windows XP, Vista, 7, 8, and 10. It encrypts files using AES 128-bit encryption and then sends a message to victims warning them that their files will be deleted within 48 hours if they do not pay a ransom.

Petya/NotPetya – affects Microsoft Windows 2000, 2003, 2008, 2012, and 2016. It encrypts files with AES 256-bit encryption and then displays a ransom note. Victims must pay a ransom of 0.5 BTC (USD 2,000) to get their files back.

Which ransomware types are most dangerous for businesses?

The most dangerous ransomware types for businesses are double-extortion ransomware, data-encrypting ransomware, and ransomware that combines encryption with data theft. Double-extortion attacks are especially disruptive because attackers encrypt business systems and steal sensitive data, threatening to publish it if the ransom isn’t paid. This can result in extended downtime, data loss, regulatory exposure, reputational damage, and financial losses.

Locker ransomware can also disrupt operations by preventing users from accessing systems or applications, while triple-extortion ransomware may add pressure by targeting customers, partners, or other third parties. Overall risk depends on the affected systems, the sensitivity of stolen data, how quickly you contain the attack, and the availability of reliable backups.

For businesses, ransomware recovery is generally more difficult when attacks involve data exfiltration, widespread network encryption, compromised backups, or lateral movement across multiple systems. Organizations can reduce these risks with immutable or offline backups, endpoint detection and response (EDR), network segmentation, multi-factor authentication (MFA), vulnerability management, least-privilege access, and a tested incident response plan.

What should an organization do immediately after detecting a ransomware attack?

1. Isolate affected systems: Immediately disconnect infected computers, servers, and network storage from the network to limit ransomware spread. Avoid shutting down systems unnecessarily because volatile evidence may be needed for investigation.
2. Contain compromised accounts: Disable suspected compromised accounts, terminate active sessions, reset affected credentials, and restrict privileged access. Review authentication logs to identify unauthorized access and prevent attackers from maintaining access.
3. Preserve evidence: Save ransom notes, malware samples, system logs, alerts, file changes, and network activity. Document affected systems and actions taken so security teams and investigators can determine the attack path and scope.
4. Activate incident response: Notify the internal security and IT teams and engage an incident response provider when necessary. Establish clear roles for containment, investigation, communication, and recovery.
5. Notify required parties: Inform management, legal counsel, cyber insurance providers, and affected stakeholders as appropriate. Regulatory or law-enforcement notifications may also be required depending on the type of data involved and applicable regulations.
6. Eradicate the threat: Identify the initial entry point, remove malicious software and persistence mechanisms, patch exploited vulnerabilities, secure accounts, and verify that attackers no longer have access.
7. Recover and monitor: Restore systems from clean, verified backups and prioritize critical business services. Closely monitor restored systems for suspicious activity, validate security controls, and document lessons learned to strengthen future ransomware defenses.

How can businesses protect backups from ransomware attacks?

Businesses can protect backups from ransomware by maintaining immutable, offline copies that attackers cannot modify or encrypt. Offline, air-gapped, or logically isolated backups provide an extra recovery layer if attackers compromise production systems and connected backup repositories. Organizations should also separate backup infrastructure from the primary network and restrict unnecessary connections between them.

Strong backup access controls are equally important. Use dedicated backup accounts, least-privilege permissions, multi-factor authentication (MFA), and separate administrative credentials to prevent attackers from deleting or altering backup data. Also monitor backup activity for unusual deletion, encryption, or configuration changes.

Businesses should regularly test backups and validate recovery procedures rather than assuming backups will work during an incident. Run scheduled restore tests, verify backup integrity, confirm you can restore critical applications and data, and document recovery procedures. Regular recovery validation helps identify corrupted or incomplete backups before a ransomware attack occurs.

How does ransomware spread across a business network?

Ransomware can spread across a business network after attackers gain access through compromised credentials, phishing, vulnerable systems, or exposed remote services. Once inside, attackers may use stolen usernames and passwords to access additional computers, servers, VPNs, or administrative accounts. Unpatched operating systems, applications, and network devices can also provide opportunities to move deeper into the environment.

Attackers can further spread ransomware through shared drives, network storage, remote desktop services, and other connected resources. During lateral movement, they may compromise additional endpoints, escalate privileges, turn off security controls, and deploy ransomware across multiple systems. This can turn a single infected device into a broader network-wide incident.

Businesses can limit ransomware propagation through network segmentation, multi-factor authentication, least-privilege access, timely patching, endpoint detection and response (EDR), secure remote access, and continuous network monitoring. Restricting access between systems and monitoring unusual authentication or file activity can help detect lateral movement before ransomware reaches critical infrastructure.

How do I know I have been infected with ransomware?

If you receive an email asking you to pay a ransom to decrypt your files, there is a good chance you’ve been infected with ransomware. Unfortunately, many people ignore these emails, thinking they’re spam. Others fall victim to phishing scams that look like legitimate messages from banks, credit card companies, etc.

If you think you might have fallen victim to a ransomware infection, here are some things to check out:

• Is your computer running slow? A ransomware attack could cause your computer to run slowly. Check your task manager to see what processes take up most of your RAM (Random Access Memory).
• Do you have trouble opening programs? Some ransomware attacks may prevent you from accessing any program except those specifically designed to decrypt your files. If you can’t open Word or Excel, you may need to use another word processor or spreadsheet program.
• Does your screen display errors when you try to access your files? If you see error messages such as “The system cannot find the path specified,” “Access denied,” or “Can not read the file,” a ransomware attack may have infected you.

You should change passwords for all accounts with sensitive information. Hackers often steal login credentials through social engineering techniques.

How can I prevent future ransomware attacks?

There are several ways you can protect yourself against future ransomware attacks:

• Use strong passwords. Strong passwords consist of letters, numbers, and special characters. Don’t reuse passwords across multiple sites.
• Avoid clicking links in unexpected places. Don’t trust messages sent via instant messaging apps. Hackers sometimes disguise themselves as friends or family members.
• Back up important data regularly. Make sure you keep copies of your files stored offsite.
• Be careful about downloading files from unknown sources. Always scan downloaded files before installing them.
• Keep your operating systems updated. Most major security updates are released every few months.
• Consider purchasing anti-malware protection. There are several types of anti-malware tools available. However, it’s best to avoid using third party products because they may interfere with other security measures.

Ransomware distribution techniques

A recent report from Symantec found that ransomware attacks were increasing by 20% per year. This was because criminals were using new techniques to distribute malware. One example is phishing emails to trick users into clicking on links that download malware onto their computers. Another technique is social engineering, where cybercriminals pretend to be legitimate organizations like banks or government agencies. They may ask victims to click on links or attachments that install malware.

Who is targeted by ransomware?

Businesses are targeted because they hold valuable information and are often easier to access than home computers. Individuals are targeted because they may not have backups of their most important documents.

Conclusion

Ransomware attacks are becoming increasingly common, often targeting business users who don’t update their systems. If you’ve fallen victim to this attack, recovering your files may be difficult without paying the ransom.

It’s important to act fast. It may seem like a lot of money to pay, but your business could lose thousands of dollars in revenue if you don’t. And if this attack hits you, it’s not just your company that will suffer – so will your family members, friends, and colleagues.