How to deal with ransomware

Ransomware attacks can bring your business to a standstill in minutes. Files are locked, critical systems are paralysed, and sensitive data may be at risk of theft or exposure. For many organisations in a live cyber security incident, the pressure to pay the ransom feels overwhelming, especially when operations grind to a halt and customers or partners are affected.

If you are reading this because you have just experienced a ransomware incident and are unsure how to deal with ransomware, stop now and contact Zensec immediately. It is not a good idea to rely on DIY solutions when dealing with a cyber incident response. Every minute counts, and attempting to resolve the attack without expert guidance could make recovery more difficult and increase the risk of permanent data loss.

For those looking to prepare or understand the threat more deeply, this blog explains what ransomware is, the immediate steps to take, and how Zensec can help you respond and recover. Our mission is to bring calm and clarity when your organisation needs it most.

What is ransomware?

Ransomware is a type of malware that prevents you from using your own systems or accessing vital business information. It does this by locking files with strong encryption or stealing data, before issuing a ransom note demanding payment. The goal of the attackers is simple: exploit your dependence on critical systems and force you to pay the ransom in exchange for a promised decryption key.

There are many ways ransomware can enter a business. The most common methods include:

• • Phishing emails – fake messages that trick employees into opening malicious links or attachments.

• • Remote desktop protocol (RDP) abuse – criminals exploit poorly secured remote access to gain entry.

• • Exploiting vulnerabilities – unpatched operating systems and applications provide easy openings.

• • Removable media – infected USB drives or shared storage devices spreading the malware.

Once inside, ransomware doesn’t just impact a single machine. The infection often spreads rapidly across affected devices, systems, mobile devices, and even enterprise networks, targeting critical assets that are essential to daily business processes.

Modern ransomware variants have become more aggressive and complex. You can view all of the top ransomware groups here. Many no longer simply encrypt files; they also carry out data theft by copying and exfiltrating sensitive company records. Threat actors then use the stolen information as leverage, threatening to release the victim’s data publicly on the dark web if the ransom is not paid. This “double extortion” method means that even if you recover from the ransomware infection, you may still face a data breach and potential regulatory consequences.

The rise of ransomware as a service has made attacks even more frequent. Here, criminal groups sell or lease ransomware kits to others, lowering the technical barrier to entry. This has created a wave of new attackers, increasing the likelihood of both large-scale incidents and highly targeted campaigns.

In short, ransomware is no longer just about locked files. It is a multi-layered threat combining malware, extortion, data exfiltration, and reputational damage. Understanding how ransomware works is the first step towards building an effective incident response plan and protecting your organisation from future attacks.

Immediate steps to take

If your organisation has been hit, speed and discipline are essential.

1. 1. Do not pay the ransom
      A ransom payment offers no guarantee. Even if criminals promise a decryption key, there’s no assurance you’ll regain access to your encrypted files or that they won’t demand more.

1. 1. Isolate infected devices
      Disconnect affected systems from the network to contain the spread. This limits damage to critical services and business processes.

1. 1. Engage your security team
      Notify your internal response team and activate your incident response plan. If you don’t have one, call our Digital Forensics and Incident Response team immediately. Our experts can guide containment and remove ransomware safely.

1. 1. Preserve evidence
      Avoid reboots or attempts to safely wipe machines. Forensic evidence in volatile memory, logs, and network traffic may identify threat actors and show how ransomware entered.

1. 1. Follow communications plans
      Prepare to brief staff, customers, regulators and insurers. Mismanaging messaging can create as much damage as the attack itself.

How Zensec helps

Our role is to bring order to chaos and ensure a clean network. With hundreds of successful responses, Zensec combines technical expertise with clear communication.

Digital forensics

We investigate how ransomware infecting your systems got in, from exploiting vulnerabilities to misused remote access. We check for other malware and uncover the full extent of compromise.

Containment and recovery

Our analysts remove ransomware and work to restore affected devices. We deploy decryption tools where available or roll back to previous versions of files. Where possible, we help you recover using secure backup and backup solutions.

Compliance support

We prepare reports for regulators and insurers, documenting the incident response and recovery. If sensitive information has been exposed, we help you manage the data publicly and mitigate reputational harm.

Strengthening defences

We reduce the risk of future ransomware attacks by improving your security posture, from multi factor authentication to patching operating systems, tightening remote access, and deploying updated antivirus software and anti malware solutions, including strategies to backup data effectively and achieve full system recovery.

Preventing ransomware

Stopping ransomware requires more than good luck. It demands proactive security.

• • Regularly test your backups and recovery processes.

• • Train staff to recognise phishing emails and attempts to trick users.

• • Monitor network traffic for signs of intrusion.

• • Restrict removable media use and apply strict controls to enterprise network access.

• • Apply security patches quickly to close gaps before ransomware attackers exploit them.

• • Enforce multi factor authentication across all accounts, particularly for remote logins.

• • Keep web browsers and endpoint protection up to date against new ransomware variants.

Can ransomware be removed?

Yes, in many cases ransomware can be removed and its effects reversed. However, success depends on the type of ransomware variant involved and the condition of your affected systems. Some older strains have publicly available decryption tools, while newer or customised variants may not yet have a known solution.

At Zensec, our responders combine multiple methods to restore operations:

• • Using advanced decryption tools when a decryption key is available.

• • Leveraging secure backup and previous versions of files to recover lost data.

• • Conducting forensic investigation to identify and safely wipe any hidden malicious code.

Even when ransom demands include threats to leak or sell sensitive information, we help you evaluate your options and take steps to minimise damage. Our goal is always to help you regain access quickly, protect your reputation, and prevent future ransomware attacks.

Why partner with Zensec?

✔ 24/7 availability – Immediate action, any time.
✔ Hundreds of recoveries – Proven success with ransomware incidents.
✔ Trusted by insurers and loss adjustors – Independent verification of expertise.
✔ Calm and clarity – Strategic support for leaders, hands-on help for IT teams, and precise guidance for compliance officers.