What Happens During a Ransomware Attack? A Step-by-Step Breakdown
Ransomware attacks have become one of the most devastating cyber threats for businesses in 2025. In a matter of hours, these attacks can encrypt critical files, lock you out of your systems, and bring operations to a standstill—all while cybercriminals demand a hefty ransom for decryption.
Understanding how a ransomware attack unfolds is the first step in preventing one. In this blog, we’ll break down what happens during a ransomware attack step by step, and share tips on how to defend your business against this growing threat.
🚨 What is Ransomware?
Ransomware is a type of malicious software that encrypts a victim’s data and demands payment (usually in cryptocurrency) in exchange for the decryption key.
✅ Fact: In 2025, the average ransomware demand for businesses has exceeded $1.8 million, with total damages in the billions worldwide.
But how exactly does ransomware infiltrate your systems and take control? Let’s break it down.
🛠️ Step-by-Step Breakdown of a Ransomware Attack
🪝 Step 1: Delivery of Ransomware Payload
The attack begins when ransomware finds its way into your organization.
Common delivery methods:
Phishing Emails: An employee clicks a malicious link or downloads an infected attachment.
Drive-by Downloads: Malware is installed unknowingly when visiting a compromised website.
Remote Desktop Protocol (RDP) Exploits: Attackers brute-force weak passwords on exposed RDP servers.
Supply Chain Attacks: Compromise through trusted software or service providers.
📈 Pro Tip: Email security and employee training are critical at this stage.
🦠 Step 2: Execution of Malicious Code
Once delivered, the ransomware executes its payload.
It uses system vulnerabilities to install itself.
Often disables antivirus or security software.
Begins reconnaissance to identify valuable files and systems.
📈 Pro Tip: Endpoint Detection and Response (EDR) solutions can detect and stop malware execution.
📡 Step 3: Spread Laterally Across the Network
Ransomware rarely stops at one machine. Modern variants like Ryuk or Conti move laterally across networks to maximize damage.
Infects shared drives, servers, and cloud storage.
Uses stolen credentials to access other systems.
Deletes backups to prevent recovery.
📈 Pro Tip: Network segmentation limits the spread of ransomware.
🔒 Step 4: Encryption of Files
Now the real damage begins.
The ransomware encrypts files with strong algorithms (like AES-256).
File extensions are changed (e.g., “.locked” or “.encrypted”).
System files are altered to prevent booting into safe mode.
📈 Pro Tip: Regular offsite backups can prevent data loss at this stage.
📝 Step 5: Ransom Note is Delivered
Once encryption is complete, the attackers leave a ransom note on infected systems.
The note usually:
Informs the victim that their data is encrypted.
Demands a ransom payment (often in Bitcoin or Monero).
Threatens data leaks or permanent data loss if the ransom isn’t paid.
Provides instructions on how to contact the attackers.
📈 Pro Tip: Never pay the ransom without consulting cybersecurity professionals—it doesn’t guarantee recovery.
💻 Step 6: Exfiltration of Data (Double Extortion)
Many modern ransomware groups don’t just encrypt data—they steal it first.
This means:
If you refuse to pay, attackers threaten to leak sensitive data online.
This “double extortion” increases pressure on victims to pay up.
📈 Pro Tip: Data Loss Prevention (DLP) tools can detect and block data exfiltration attempts.
⏳ Step 7: Ransom Payment and Recovery (Optional)
If the victim pays:
They may receive a decryption key to recover their files.
However, many businesses report receiving keys that don’t fully work.
If the victim doesn’t pay:
They must recover from backups or rebuild systems from scratch.
📈 Pro Tip: Incident Response (IR) teams can help recover systems and negotiate with attackers if necessary.
🛡️ How to Protect Your Business From Ransomware
✅ 1. Implement Strong Email Security
Phishing is the #1 delivery method for ransomware.
✔ Use advanced email filters to block malicious emails.
✔ Train employees to recognize phishing scams.
✅ 2. Backup Your Data Regularly
✔ Follow the 3-2-1 rule (3 copies, 2 media types, 1 offsite).
✔ Test backups to ensure they’re not infected.
✅ 3. Use Endpoint Protection and EDR Solutions
✔ Detect and isolate infected devices early.
✅ 4. Patch Systems Promptly
✔ Apply security updates to close known vulnerabilities.
✅ 5. Restrict Access and Segment Networks
✔ Limit user permissions and use network segmentation to contain infections.
✅ 6. Engage a 24/7 Security Operations Center (SOC)
✔ Continuous monitoring detects and stops attacks before encryption.
🌐 How Factosecure Can Help
At Factosecure, we specialize in ransomware prevention and incident response:
✅ 24/7 monitoring through our SOC as a Service
✅ Rapid response to contain and recover from ransomware attacks
✅ Employee training and phishing simulations
✅ Backup and disaster recovery planning
📞 Don’t Wait Until It’s Too Late
Ransomware can strike at any moment. Protect your business with proactive measures and expert support from Factosecure.