Survivre aux ransomwares : Comment se préparer à l'inévitable

With ransomware attacks hitting businesses every 11 seconds, falling victim to a ransomware attack isn't a question of if—it's when.

In the face of this threat, we at Object First wanted to not only spread awareness of the threat of ransomware, but also provide solid strategies to help businesses prepare for—and recover from—actual ransomware attacks.

This blog offers a summary of all the key risks your business might face, as well as solid strategies to combat them—and ensure recovery when an attack does happen.

Understanding Ransomware

Modern ransomware has evolved far beyond simple file encryption. It now comes in a huge range of variants—from crypto ransomware that encrypts files requiring a decryption key, to locker ransomware that locks users out of entire systems, and double extortion attacks that both encrypt and steal data, threatening to leak sensitive information.

The rise of Ransomware-as-a-Service (RaaS) has made sophisticated attacks accessible to less skilled criminals, increasing the attack surface.

The typical attack pattern includes gaining initial access through phishing emails or exposed remote services, escalating privileges to gain administrative control, moving laterally across networks, and finally deploying encryption across the entire environment while demanding cryptocurrency payments.

The real kicker in modern ransomware is that it targets backup systems in 96% of cases, meaning you could not only lose your data, but any hopes of recovery, too, leaving your business completely inoperable. The harsh reality is many organizations that can't recover their data simply don't survive.

How to Survive an Attack

The process of preparing for a ransomware attack—and ensuring recovery—consists of six key steps:

1. Preparation and Prevention: Building Your Defense

Effective ransomware defense starts long before any attack occurs, and revolves around three main axes: people, processes, and technology.

• People: Organizational readiness begins with establishing clear roles and responsibilities—especially those who need to handle crisis communications and strategic decisions under pressure.

• Processes: Firstly, building a solid incident response plan is essential. This plan outlines the exact steps that will be taken in the case of a ransomware attack. The plan should then be stress-tested with regular tabletop exercises that simulate real-world attacks, helping teams identify gaps and improve coordination.

• Technology: Strengthening your hardware itself is the foundation of your efforts here. You should look to implement Zero Trust Data Resilience principles, including network segmentation, least privilege access, and multi-factor authentication across all systems. Endpoint Detection and Response solutions provide valuable visibility, while securing remote access points helps close common entry vectors.

Software has a role to play, too: patch management needs to be handled rigorously, with regular updates for operating systems, applications, and firmware. Since phishing remains a top ransomware vector, email security is also crucial: look to enhance anti-phishing protocols and implement widely available advanced scanning tools.

Last but not least: don’t forget your backups. A good backup strategy serves as your last line of defense. The traditional 3-2-1 backup rule—three copies of data, on two different media types, with one stored offline—provides basic resilience.

However, modern threats require truly immutable storage that prevents modification or deletion even with administrative access.

2. Detection and Early Warning: Spotting Trouble

Early detection of a ransomware attack can make the difference between a minor incident and a catastrophic breach.

To detect threats effectively, organizations need monitoring systems that combine behavioral analysis, threat intelligence, and centralized visibility to identify threats before ransomware deploys.

The system should be set up so that key Indicators of Compromise (IOCs) trigger immediate investigation and containment procedures. This could include things like abnormal file access patterns, sudden spikes in CPU or disk usage, outbound connections to malicious domains, or attempts to disable security tools.

Proper monitoring also requires centralized logging, especially things like Security Information and Event Management (SIEM) systems, endpoint activity monitoring—as well as logging alerts from antivirus, EDR, and firewalls.

Finally, leveraging threat intelligence enhances an organization's ability to anticipate ransomware campaigns through external threat feeds, updated blacklists of malicious IPs and domains, and mapping threats to established frameworks to improve ransomware detection strategies.

3. Incident Response (IR): Your Critical First Hours

When ransomware strikes, the first few hours are paramount. Immediate priorities during the first couple of hours include:

• Identifying and isolating affected systems

• Physically disconnecting compromised devices from the network

• Preserving forensic evidence

• Activating your incident response plan

Throughout these steps, communication is vital, both inside and outside of the organization. Teams should use secure channels internally to avoid potentially compromised internal systems.

As for external communication, it’s important to engage with legal counsel and law enforcement as quickly as you can so you can ensure legal compliance throughout your response and manage reputational risk. You’ll also need to inform your customers as early as practicable.

Remember to contact insurance providers, too. Organizations should have pre-vetted incident response firms ready to assist and notify cyber insurance providers immediately, since many policies require prompt reporting to activate coverage.

Above all, avoid acting rashly: don’t delete files or logs that could be crucial for investigation, don't power off systems unless advised by professionals, and avoid direct engagement with attackers without legal guidance.

4. Containment and Eradication: Stopping the Damage

Swift containment prevents further damage, while thorough eradication ensures a clean recovery environment.

• This process starts with understanding how the attack occurred: identifying the ‘patient zero,’ determining the specific attack vector, and mapping lateral movement paths to understand how attackers gained access.

• The next step is to contain the actual damage. Strategies include implementing network quarantine to isolate infected systems, disabling compromised accounts, and applying DNS and firewall rules to block malicious domains and IP addresses.

• Finally, complete eradication requires removing all malware artifacts using trusted security tools, potentially reimaging systems to ensure complete removal of persistent threats and changing all credentials—especially high-privilege accounts—to prevent re-entry.

5. Recovery and Restoration: Getting Back to Business

Once the immediate threat of a ransomware attack is dealt with, you can move from containment to restoration and disaster recovery.

It starts with system recovery—a methodical approach that prioritizes core systems first, verifies backup integrity, identifies the last known clean restore point, and gradually reintroduces systems while monitoring for anomalies.

Then comes post-incident validation: confirmation that threats have been fully eradicated through scanning, monitoring for reinfection using ransomware detection tools and network monitoring, and reviews logs for lingering indicators of compromise.

Documenting your actions is really important in this phase, too. It creates a detailed incident timeline outlining key events and decisions, while fulfilling regulatory notification requirements maintains compliance with legal standards.

This documentation will also be invaluable for insurance claims, any relevant legal proceedings, and preparation for future threats.

6. Post-Incident Activities: Learning and Improving

The very end of a ransomware incident is about analysis, improvement, and compliance to strengthen organizational resilience against future threats.

Comprehensive forensic investigation should be conducted to determine the full scope of the attack, identify the initial point of compromise, understand attacker methods, and pinpoint security weaknesses that were exploited. These insights are vital for preventing recurrence.

A structured ‘lessons learned’ review with all relevant stakeholders provides an opportunity to evaluate incident response effectiveness, identify procedural gaps, and assess decision-making under pressure.

Organizations should update their incident response playbooks, revise security policies, and implement necessary changes based on these findings.

You will also need to navigate regulatory and legal obligations, potentially reporting incidents to regulatory bodies and conducting legal assessment of any ransom payments.

Effective post-incident response requires coordination with incident response firms, cyber insurance providers, legal counsel, and law enforcement agencies.

Conclusion: Assume Breach, Prepare for Recovery

Ransomware is a matter of when, not if, and every component of an organization must be equipped to recognize, respond to, and recover from an attack.

The most successful organizations adopt an "Assume Breach" mindset, focusing on minimizing impact and ensuring rapid ransomware recovery rather than hoping to prevent all attacks. This includes treating backup systems as critical infrastructure, regularly testing incident response procedures, and building security into every system and process.

Resilience isn't a one-time achievement—it's an ongoing commitment requiring continuous assessment, staying informed about emerging threats, and fostering a culture of preparedness. The investment in ransomware preparation is far less than the cost of a successful attack that brings your business to a standstill.

Don't wait for the inevitable. Start building your ransomware defense today, because when the attack comes, your preparation will determine whether you recover in days or never recover at all.

Ready to dive deeper? Download our complete Ransomware Survival Guide for more detailed technical guidance, step-by-step response procedures, checklists, and additional implementation strategies to ensure your organization is truly prepared for when ransomware strikes.