What Is Ransomware? How It Works and How to Protect Yourself in 2026
Imagine starting your computer one morning—only to be greeted by a bold ransom note instead of your usual desktop. All your photos, documents, and important files are locked and inaccessible. This is the work of ransomware, a particularly damaging type of malware.
In this article, we’ll explain what ransomware is, how to spot an attack, and what to do if it happens to you.
Ransomware is malware that encrypts your files or locks you out of your computer. Attackers demand payment—usually in cryptocurrency like Bitcoin—to unlock them.
Common infection vectors include phishing emails with malicious attachments, fake websites, and outdated software with unpatched security flaws.
If you’re hit, immediately disconnect the device from the network, take screenshots for evidence, and file a police report. Security authorities generally advise against paying the ransom—there’s no guarantee you’ll get your files back.
There’s no such thing as 100% protection against ransomware, but you can lower your risk. Keep your operating system and all software up to date, and use a firewall along with up-to-date antivirus software.
You should also back up your important files regularly. That way, you can restore your data if ransomware strikes.
What Is Ransomware?
Ransomware is a type of malicious software (malware) that holds your files hostage. The name combines “ransom” and “software.” It’s also called “crypto-malware.”
Here’s how it works: many ransomware variants encrypt important files so you can’t open or use them. Attackers then demand payment, usually in cryptocurrency like Bitcoin, which is harder to trace, to unlock your data.
Types of Ransomware
Not all ransomware works the same way. Over the years, cybercriminals have developed different versions, each with its own methods and level of threat.
Encryption Ransomware (Crypto-Ransomware)
This is the most common and dangerous type. It encrypts files like documents, photos, and videos while leaving the operating system working so you can read the ransom demand and pay. Modern ransomware often uses strong encryption that is generally impractical to break without the decryption key.Locker Ransomware
Locker ransomware doesn’t encrypt individual files. Instead, it locks you out of your entire operating system. When you start your computer, all you see is a ransom note, and everything else is blocked. In some cases, it may be possible to recover the system by booting from an external drive or removing the hard drive.Double Extortion
In double extortion attacks, criminals steal your data before encrypting it. Even if you have backups and refuse to pay, they threaten to leak or sell your sensitive information, which is especially damaging for businesses.Ransomware-as-a-Service (RaaS)
Cybercriminals now rent out ready-made ransomware kits to other attackers, complete with “customer support.” Ransomware-as-a-Service has contributed to a broader increase in ransomware activity.
Well-Known Ransomware Attacks
The first documented ransomware attack dates back to 1989. Biologist Joseph Popp mailed 20,000 infected floppy disks to attendees of an international AIDS conference held in Stockholm. The malware hid directories and encrypted filenames on victims’ PCs.
Victims were told to mail $189 to Panama to restore their files. But the encryption was crude, and experts cracked it quickly.
Since the 2000s, ransomware has become a growing threat. Here are some of the most notorious attacks that made headlines worldwide:
Name | Key Details | Estimated Damage |
|---|---|---|
WannaCry (2017) | Exploited an NSA security flaw, infecting over 230,000 computers in 150 countries within days. It severely disrupted hospitals across the UK’s National Health Service (NHS), forcing some to cancel operations and appointments. | About $4–8 billion |
NotPetya (2017) | Though disguised as ransomware, NotPetya was actually designed to permanently destroy data. It spread worldwide through a compromised software update for M.E. Doc, a widely used Ukrainian accounting application. | About $10 billion |
Emotet | Originally a banking trojan, it grew into one of the world’s most dangerous malware networks and opened the door to other ransomware attacks. | Several billion dollars |
LockBit | A prolific cybercriminal group offering ransomware-as-a-service, widely believed to have operated from Russia. They target organizations and demand ransom payments. | Hundreds of millions of dollars |
Colonial Pipeline | A ransomware attack on the Colonial Pipeline (the largest fuel pipeline in the United States) caused widespread fuel shortages across the East Coast and led the company to pay a $4.4 million ransom. | Millions of dollars in damages |
How Does Ransomware Get on My Device?
Many ransomware attacks begin with user interaction, such as opening malicious attachments or clicking deceptive links. Once you know the common ways ransomware gets onto your computer or network, you can lower your risk significantly.
Here are the most common ways ransomware infects devices:
Phishing emails
Cybercriminals send emails that look like they come from trusted sources—your bank, the IRS, a shipping carrier, or a colleague. These emails often carry malicious attachments disguised as invoices or other important documents, or links to fake websites. In some cases, a single click can trigger the attack.Infected websites and drive-by downloads
Just visiting a compromised website can silently install malware through browser or plugin vulnerabilities. Even legitimate sites are at risk if attackers hide malicious code in ads (malvertising).Unsecured remote desktop connections
Attackers actively hunt for poorly secured remote access points, especially in remote work setups. Weak passwords are the main problem. Once they get in, they can install ransomware by hand.Infected USB drives and external storage
USB drives and external storage devices can carry malware. Connecting an infected storage device may introduce malware onto the system.Outdated software and missing updates
Outdated software is a common target for attackers. WannaCry spread so widely because many systems hadn’t installed a security patch that had been available for months. Unpatched operating systems, browsers, Microsoft Office applications, and server software are especially vulnerable.
How Can I Spot Ransomware?
Ransomware is sneaky. You often don’t notice it until it’s too late. But not every computer glitch means malware, and there are some telltale signs to watch for.
One early red flag is files with strange extensions like .locked, .crypt, .encrypted, or .a1b2c3 that suddenly won’t open. Other signs include unusually high CPU or disk usage, disabled antivirus software, or heavy network traffic to unknown servers. These don’t always mean ransomware, but they’re worth checking.
A ransom demand is a strong indicator that the system has been compromised by ransomware.
What to Do If You’re Hit by Ransomware
If you spot a ransomware attack, stay calm and act fast. Every minute counts.
Important: Avoid rebooting the device unless instructed by an IT or security professional, as some ransomware variants may continue or complete their encryption process after a restart.
Here’s what to do next:
1) Disconnect from the network immediately
Turn off Wi-Fi or unplug the network cable first. This stops the malware from spreading across your network.2) If possible, preserve the encrypted files
Copy the encrypted files to an external drive (USB stick, hard drive) and disconnect it from your computer. Be careful with cloud storage that syncs automatically, since encrypted files could overwrite your clean backups.3) Document the evidence
Take screenshots of the ransom demand and note which files or systems are affected. You’ll need this for later analysis and for reporting to authorities.4) File a report and notify authorities
Report the incident to your local law enforcement and file a complaint with the FBI’s Internet Crime Complaint Center (IC3) at ic3.gov. You can also report to the Cybersecurity and Infrastructure Security Agency (CISA) at cisa.gov.5) Identify and remove the ransomware
If this is a personal device and no critical data is at risk, you may be able to remove the ransomware yourself and then decrypt your files. Use tools like NoMoreRansom.org and an anti-malware tool. Follow our step-by-step guide for help:
If you’re unsure or the malware has already spread across your network, get professional help right away.
No. Official agencies like the FBI and CISA strongly advise against paying. Paying may encourage further criminal activity and does not guarantee data recovery.
For more details, visit the FBI’s ransomware page at fbi.gov/ransomware.
How Can I Protect Myself From Ransomware?
Reducing your exposure to common attack vectors is one of the most effective ways to lower your risk. Keep your system updated, and use a firewall and antivirus software. Both Windows and macOS include built-in security features such as firewalls and malware protection. For extra security, you can add third-party antivirus programs.
Follow basic online safety practices: Be careful with suspicious emails, especially those with attachments. Don’t click links without thinking, and only download software from trusted sources. When in doubt, don’t open attachments or share sensitive information.
Because ransomware targets your personal files, we also recommend regular backups. Store them on an external drive. This matters because even after you remove the ransomware, encrypted files generally cannot be restored without backups, a decryption key, or a compatible recovery tool.
For more tips, refer to our detailed guide on how to prevent ransomware:
Final Thoughts: How to Stay Safe From Ransomware
Ransomware isn’t just a problem for big companies anymore. It can affect individuals, small businesses, and large organizations alike. But with regular backups, up-to-date software, and careful habits—like watching out for suspicious emails and downloads—you can lower your risk.
If it happens, stay calm. Disconnect the device from the network right away, and get professional help if you need it. Never pay the ransom, since paying the ransom may encourage further criminal activity without guaranteeing that your files will be restored.
Frequently Asked Questions
Ransomware is malicious software that encrypts the files on an infected device, locking you out of them. Attackers then demand a ransom, usually in cryptocurrency, in exchange for the decryption key. Common infection methods include phishing emails, infected downloads, or security flaws.
Watch for files that won’t open or have unfamiliar extensions (like .locked or .encrypted), a ransom note on your screen, a computer that suddenly runs very slowly, or antivirus alerts. In some cases, your desktop is replaced with a lock screen from the attackers.
Recovering from a ransomware infection typically involves two separate steps: getting rid of the malware and restoring your files. First, disconnect your computer from the network to keep the malware from spreading.
Then restart in safe mode and use an anti-malware scanner to remove the infection. Afterward, check nomoreransom.org to see if a free decryption tool exists for your specific ransomware strain.
No. Authorities and cybersecurity experts strongly advise against it. Paying doesn’t guarantee you’ll get your files back; it funds future attacks, and it marks you as a target for more ransomware.
