Medusa ransomware Gang Advisory – How to stay safe from the rising threat

A wave of cyberattacks in early 2025 prompted companies worldwide to reassess their security strategies. The ransomware group is at the heart of this cyberattack surge. The risk is so serious that the FBI, CISA, and MSISAC have released a Joint Cybersecurity Advisory warning organizations to take immediate action.

What is the ransomware advisory about? What can you do, more importantly, to protect your business, yourself, and your data?

We’ll break it down into simple everyday language. No jargon. Just straight talk.

What is the Medusa Ransomware Gang advisory?

The Medusa ransomware gang is a ransomware-as-a-service (RaaS) group that first appeared in mid-2021. By 2025, they were one of the top 10 global ransomware threats. They had over 300 organizations affected, with attacks increasing every year.

The warning issued in March 2025 is a serious alert. According to the FBI and CI, SA, the Medusa group employs a “double-extortion” strategy. They not only encrypt files but also steal your sensitive data. Then they threaten to release it publicly until a payment is made.

Imagine one morning waking up to discover that all of your files are locked and that your client data is being sold on the dark net. This gang is bringing to life the nightmare of having all your work files locked and your customer data for sale on the dark web.

Who is the Medusa ransomware gang

The Medusa Ransomware Gang is not just another hacker group. They are professional hackers who use a RaaS Model, where affiliates perform attacks and split profits.

The following are some key facts.

• Believed to be operating from Russia and its allies

• Not related to MedusaLocker or Medusa Mobile Malware

• Linked to an eCrime Group called The Frozen Spider

• Keeps a Dark Web blog to shame publicly non-paying victims

Their targets? Their targets?

Context is important when it comes to the recent surge in ransomware attacks.

The first quarter of 2025 witnessed 2,289 ransomware attacks, a 126% increase over the same period in 2018. In 2024, law enforcement disrupted groups such as LockBit and AlPHV. This power vacuum led to the rise of new actors such as Medusa.

According to Check Point, the ransomware group remains the most active, but Medusa has been gaining ground quickly.

Medusa’s Tactics, Techniques, and Procedures (TTPs).

The Medusa gang advisory highlights several dangerous TTPs that attackers use:

• • Initial Access: Phishing attacks, credential stuffing, and unpatched vulnerabilities

  • Living Off the Land (LoTL): Use PowerShell and WMI to avoid detection

  • Data exfiltration: Before encrypting the data, they steal it by using a secure Tor channel

  • Encryption Files are renamed using the . MEDUSA Extension

  • Ransom Note: Victims receive a file titled !!! READ_ME_MEDUSA!! .txt

• Leaked Site: Noncompliant victims exposed on the Medusa blog

How to Protect Against Medusa Ransomware

This guide will help you protect your system based on the most recent advice from experts.

1. Create an Effective Backup Plan

Store backups in a separate, safe location. Cloud backups are not enough.

2. Use Strong Authentication

Implement a NIST-compliant password policy.

3. Update Your System Immediately

As soon as security updates are available, you should apply them. Vulnerabilities can be the first point of entry.

4. Segment Your Network

Segmenting your network will limit lateral movement. Once inside, don’t let attackers move around freely.

5. Monitor Network Behavior

Use endpoint detection (EDR) to detect unusual behavior.

6. Use Secure VPNs

If you have employees who work remotely, make sure they are connected via secure, encrypted VPNs.

7. Audit user privileges

Use the principle of least privilege—users should only have access to what they need.

8. Filter Traffic

Block traffic coming from IPs and locations that you suspect.

Your first line of defense is to train your employees.

The majority of ransomware attacks start with an email phishing. Training in security awareness should not be negotiable.

Use platforms like Adaptive Security to:

• Train your employees with engaging content that is based on real-life situations

• Test your awareness by running phishing simulations

• Analyze the results and customize future training

Consider it a fire drill – better to practice than the real thing.

Level up with Check Point Harmony Endpoint

Consider Check Point’s Harmony Endpoint to protect your business from ransomware threats such as Medusa.

What it offers

• Endpoint protection

• Automated Attack Detection

• Fast Recovery Options

• cost-effective customizable

Experience the protection for yourself by booking a demo.

Final Thoughts

The Medusa gang advisory does not represent just another technical bulletin. This is a wake-up message. The ransomware threat is becoming more sophisticated, dangerous, and sneaky. But with the right tools and awareness, you can keep up.

Prevention is less expensive (and more painful) than the recovery process.

“Just like in cloud environments explained in RealtyMe SA Cloud Computing, strong data protection practices are also essential when facing ransomware threats like Medusa.”

FAQ: Ransomware Basics

What is ransomware, and how can I tell if it’s in my system?

Signs include

• Your files or system is locked out

• Ransom notes are displayed on your computer screen or in folders

• File extensions suddenly become .MEDUSA

• Strange Activity in Your System Logs

If you suspect an infection, use malware detection software or contact a professional in cybersecurity.

Is Medusa safe?

No, Medusa Ransomware can be extremely dangerous. It steals and encrypts data to extort money. You shouldn’t interact with this tool or software unless you are a security researcher working in a controlled setting.

How easy is it to remove ransomware?

Unfortunately, no. If your files have been encrypted, you can’t fix them unless you use a decryptor or clean backups. There’s also no guarantee that you will get your data even if the ransom is paid.

Can ransomware be prevented?

Yes—with layers of protection.

• Patching software is recommended regularly.

• Train your staff to be aware of phishing

• Strong passwords and MFA

• Data backup is not available

• Advanced endpoint security tools

You can reduce your risk by taking these steps.

Keep informed. Keep informed. Stay informed.