What you'll learn in this article
Learn the top 10 best practices every organization should follow to prevent ransomware attacks and minimize their impact:
- Ransomware often enters through phishing emails, so employee awareness, advanced email security, and multi-factor authentication are essential defenses.
- Regular software updates, strong backup procedures, limited user access, and endpoint protection help reduce vulnerabilities and contain attacks.
- Segmenting networks, monitoring traffic, and having a tested incident response plan create a layered, resilient defense against ransomware.
Ransomware is no longer a distant threat. It’s a present risk that affects organizations of every size, across every industry. In just minutes, it can encrypt critical systems, disrupt business operations, and put your data in someone else’s control.
This article outlines 10 proven strategies for how to prevent ransomware attacks. Whether you’re leading cybersecurity for an enterprise or managing risk for a growing team, these are practical, priority-driven steps you can start implementing today.
Mimecast has supported over 42,000 organizations with security that’s designed to be adaptive, integrated, and ready for what’s next. These recommendations reflect that experience along with the evolving threat patterns we track every day.
What causes ransomware?
At its core, ransomware spreads through user interaction, usually from an email that looks legitimate.
The most common attack methods include:
- Phishing emails with a malicious attachment
- Fake invoices, shipping updates, or login requests
- Social engineering tactics, such as urgency or impersonation
These entry points are often small and easy to overlook. But once clicked, the consequences are significant. The malware installs quietly, encrypts files, and demands payment. In some cases, attackers also extract sensitive data to increase pressure through double extortion.
Understanding these tactics helps clarify where ransomware prevention efforts should begin: with people, process, and visibility.
10 best practices to prevent ransomware for organizations
Here are the 10 best practices on how to prevent ransomware for every organization:
- Regularly Update Software and Systems
- Implement Robust Backup Procedures
- Implement Robust Backup Procedures
- Use Multi-Factor Authentication (MFA)
- Deploy Advanced Email Security Solutions
- Restrict User Access and Privileges
- Implement Endpoint Protection and Detection
- Segment and Isolate Critical Network Areas
- Monitor Network Traffic and Use SIEM Tools
- Develop and Test a Ransomware Incident Response Plan
1. Regularly update software and systems
It sounds simple, but outdated or malicious software is one of the most common ways ransomware gains unauthorized access.
Attackers often exploit known vulnerabilities in:
- Operating systems
- Third-party applications
- Browser plugins
- Email clients
To reduce exposure, it’s best to:
- Use automated patching tools to maintain consistency across systems
- Prioritize critical updates, especially for externally exposed services
- Regularly audit your software inventory to spot overlooked assets
Maintaining current versions of software is a fundamental part of cyber hygiene, helping eliminate weaknesses that are frequently targeted during a ransomware attack.
Don’t let a missed patch become your weakest link.
2. Implement robust backup procedures
When all else fails, backups become your fallback. But to be effective, backups must be:
- Encrypted, to protect sensitive content
- Stored offline or off-network, so they can’t be encrypted by ransomware
- Tested regularly, to ensure they’re accessible and intact when needed
Best practice is to follow the 3-2-1 rule:
- Maintain 3 total copies of your data
- Store them on 2 different media types
- Keep 1 copy offsite or offline
Backing up is only part of the job. Recovering quickly is the goal.
3. Educate employees on securityawareness
Ransomware often enters through a single click. That’s why awareness training is a key layer of defense.
Most users don’t intend to cause harm. But without training, they might not recognize a suspicious email, link, or attachment.
Effective programs should:
- Focus on real-world phishing examples, not abstract potential threats
- Include simulated attacks to track progress and highlight risk
- Reinforce good habits with timely, relevant feedback
Mimecast’s Security Awareness Training tailors education to each user—helping security teams support their employees, not overwhelm them.
When users are aware and engaged, they’re far more likely to pause and question something suspicious.
4. Use Multi-Factor Authentication (MFA)
Strong passwords are helpful. But if compromised credentials are stolen—and they often are—MFA provides a critical second layer of defense.
It’s especially important for:
- Remote access
- Email accounts
- Admin tools
- Cloud services
Use methods like:
- Authenticator apps (e.g., Microsoft Authenticator, Duo)
- Hardware tokens
- Biometric logins, where supported
Avoid relying solely on SMS-based MFA when possible, as it can be vulnerable to SIM-swapping attacks.
Implementing MFA across your critical systems is one of the most reliable ways to stop account-based cybersecurity threats before they escalate.
5. Deploy advanced email security solutions
Email remains the most common delivery method for ransomware.
Basic spam filters often miss advanced phishing attempts—especially those using:
- Compromised third-party services
- Payloads hidden in documents or zipped folders
- Time-based or “at-click” redirects
A modern email security platform should provide:
- Real-time URL scanning
- Attachment sandboxing
- Anomaly detection powered by AI
- Threat intelligence from global sources
Mimecast’s advanced email security is built specifically to block targeted attacks—before they reach the inbox. That means fewer false positives, better visibility, and less reliance on end-user instincts alone.
6. Restrict user access and privileges
The fewer privileges a ransomware-infected user account has, the less damage it can do.
Apply the principle of least privilege:
- Users should only have access to what they need to perform their role
- Admin rights should be restricted, temporary, and closely monitored
- Access permissions should be reviewed regularly, especially after role changes
Use Privileged Access Management (PAM) solutions to enforce controls and log activity.
This isn’t just about limiting risk—it’s about improving auditability and control across the organization.
7. Implement endpoint protection and detection
Endpoints are where many attacks begin, especially in hybrid and remote work environments.
Modern endpoint protection should go beyond signature-based antivirus. Look for tools that provide:
- Behavioral detection (e.g., spotting unusual file encryption or process behavior)
- Policy enforcement
- Automated response, such as device isolation
For more advanced visibility, deploy Endpoint Detection and Response (EDR):
- Continuously monitors endpoint activity
- Alerts security teams to early indicators of compromise
- Anomaly detection powered by AI
- Helps investigate and contain incidents faster
Mimecast integrates with leading EDR platforms to provide broader context, linking endpoint activity with email, user identity, and cyber threat data.
8. Segment and isolate critical network areas
If an attacker gains a foothold, network segmentation can prevent that threat from spreading laterally.
Key steps include:
- Separating systems that store sensitive data (e.g., financial records, IP, PII)
- Using VLANs and access control lists (ACLs) to define boundaries
- Limiting communication between segments to essential workflows
Add controls such as internal firewalls and network access policies for additional protection.
Segmentation also helps with containment and investigation, making it easier to trace and isolate unusual activity.
9. Monitor network traffic and use SIEM tools
Detecting ransomware early depends on visibility.
Look for:
- Unexpected traffic patterns (e.g., large data transfers, strange destinations)
- Unusual authentication activity
- Repeated failed login attempts
Network monitoring solutions and Security Information and Event Management (SIEM) tools help centralize this data so patterns emerge quickly.
SIEM platforms can:
- Aggregate logs from multiple systems
- Correlate events for faster detection
- Trigger alerts based on defined thresholds or behavioral baselines
Mimecast’s intelligence feeds and integrations enrich these systems with high-confidence signals. Our platform gives your team faster, more actionable insights.
10. Develop and test a ransomware incident response plan
Preparation is what separates a manageable incident from a major disruption.
A ransomware response plan should include:
- Roles and responsibilities (security, IT, legal, executive, communications)
- Steps for containment, investigation, and recovery
- Contact points for law enforcement and cyber insurance providers
Test your plan regularly:
- Conduct tabletop exercises
- Run through real-world scenarios
- Document lessons learned and update workflows accordingly
Mimecast’s Email Continuity ensures access to communication even if primary systems are compromised, keeping teams connected during a critical moment.
Planning ahead brings clarity in high-pressure situations. It also improves response time and reduces overall impact.
Conclusion
Preventing ransomware isn’t about one tool or tactic. It’s about building a layered, resilient security strategy—one that combines technology, process, and people.
To recap:
- Keep systems updated and backed up
- Educate employees and reduce human risk
- Enforce MFA and email security
- Limit access and secure endpoints
- Monitor networks and plan ahead
At Mimecast, we help organizations take these steps with confidence. Our integrated platform brings together email protection, user training, threat detection, and data continuity so you can defend against ransomware at every stage.
