Cyberattacks happen. What you do afterward can affect your cybersecurity posture for years to come. But it can also affect your ongoing success as a business, your good name and your compliance with the laws that govern your industry. You can only realize the full benefits of cybersecurity with the one-two punch of strong proactive and reactive cybersecurity.

Proactive Versus Reactive: It Takes Both

We detailed the proactive approach in a previous article. Next, explore what to do in the aftermath of an attack.

Reactive cybersecurity is one of the most important elements in your cybersecurity strategy. It comes in four stages, and each is as vital as the others.

Contain the Breach

First, find out which servers and devices the attack affected, disable remote access to them and disconnect them — or disconnect all systems if you’re not exactly sure.

Next, change all passwords in the organization right away, making sure your new passwords are strong.

Keep your firewall settings in place. But don’t delete anything until you have concluded your investigation into the attack. After all, you need to preserve all evidence.

Last but not least, install security updates on all systems that you can update.


At the next stage, investigate the attack and find out how widespread it was, who might be involved and what actions by employees or security tools enabled it to occur. Figure out the timeline, and when the attack began. (After all, it could be months ago). Find out what the attackers removed from your systems. Determine the scope and scale of the attack. This includes assessing the damage monetarily, to your reputation and in other ways. Consider a third-party audit of your systems.

Find the malware or ransomware, and every other source of code left behind by the attackers.

Figuring out who had access to the affected resources will also help. After all, this will help direct communication about remedies, training and other solutions.


Consult with your organization’s attorneys and work with them on the messaging about the breach.

Assess who the attack might have affected, including employees, managers, partners, customers and vendors. This is a chance to stand and deliver real transparency to stakeholders, which builds trust in a bad situation. Inform them right away with follow-ups as you uncover big pieces of new information. Pay special attention to the question of whether the attack has directly affected each recipient, and exactly how.

Set up a hotline for stakeholders to call with any questions about the cyber attack, and make sure all messaging includes an invitation to call.

Contact law enforcement. Cyberattacks are against the law and you should contact the relevant authorities, such as the FBI.

Contact and update your insurance provider. Consider them a partner and get their advice on how to proceed with forensics and documentation.


Gather up all findings from the postmortem follow-up and craft a full report detailing what happened, when it happened, why it happened, who did it, who is affected and what steps you’re taking to prevent such attacks in the future.

Update training, policies and procedures. Find out what tool or set of tools is needed to make sure systems aren’t breached again.

Good Cybersecurity Posture for Next Time

Proactive versus reactive isn’t always an issue of one or the other. While proactive cybersecurity measures are vital, reactive cybersecurity is equally important. It’s not just about recovery. It enables you to:

  • Protect systems and data from more loss or theft
  • Find out what happened and why
  • Demonstrate transparency and competence to all stakeholders
  • Comply with regulations
  • Make sure it doesn’t happen again.

This is where you can cultivate real cybersecurity, a process that takes place over time. Do your all to prevent cyberattacks at the moment. But then do your all to prevent future cyberattacks too by doing reactive cybersecurity right!

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