Cuba Ransomware: Complete Guide

Cuba ransomware has been attacking businesses since 2021. Its main spreading technique is through known software vulnerabilities that still need to be patched. Cuba ransomware is also distributed through phishing emails and social engineering techniques, and once it infects a system, it can cause significant damage and disruption to operations.

The ransomware has continued to evolve and adapt over time, with the ability to bypass security measures and encrypt files on infected systems. This article will take a closer look at the Cuba ransomware, its attack methods, and recommended prevention and mitigation strategies.

What kind of malware is Cuba?

Cuba is ransomware, which is a type of malware. Despite its name, the ransomware has no known relations with the Republic of Cuba.

Once Cuba infects a machine, it encrypts the files adding the .cuba file extension to them. Then it drops a ransom note threatening the victim by stating the only way to restore the files is by paying the ransom.

As with most current ransomware, Cuba threat actors use the double extortion technique in which they also threaten to leak the stolen data if the ransom is not paid.

Everything we know about Cuba ransomware

This list contains the basic information about the new ransomware strain known as Cuba as released by CISA.

Confirmed Name

• Cuba ransomware

Threat Type

• Ransomware
• Crypto Virus
• Files locker
• Double extortion

Encrypted Files Extension

• .cuba

Ransom Demanding Message

• !!FAQ for Decryption!!.txt

Detection Names

• Avast Win32:Malware-gen

• AVG Win32:Malware-gen

• Emsisoft Trojan.GenericKD.46283436 (B)

• Kaspersky Trojan-Ransom.Win32.Cuba.h

• Malwarebytes Malware.AI.1342047581

• Microsoft Ransom:MacOS/Filecoder

Ransomware family, type & variant

Cuba is a ransomware family with variants that have their own file encryption. It’s believed that Cuba is Ransomware as a Service.

Distribution methods

• Software vulnerabilities
• Zero-day vulnerability
• Phishing emails
• Malicious email attachments
• Social engineering

Consequences

• Data exfiltration
• File encryption

Is There a Free Decryptor Available?

No. There is no known public decryptor for Cuba ransomware available at this time.

Cuba ransomware IOCs

Indicators of Compromise (IOCs) are artifacts observed on a network or in an operating system that indicate a computer intrusion with high confidence. IOCs can be used for early detection of future attack attempts using intrusion detection systems and antivirus software.

The known IOCs of Cuba ransomware include:

• Files with .cuba extension. Encrypted files will have a .cuba extension added to their original file name.
• Ransom note. The attacker will typically leave a ransom note that explains what has happened and demands payment in exchange for the decryption key.
• Inability to open files. Encrypted files will be unable to be opened or accessed, as they are locked by the malware.
• Pop-up messages. The attacker may display pop-up messages or warning windows indicating that the victim’s files have been encrypted and demanding payment.

How do you find Cuba ransomware’s ransom note

The Cuba ransom note is short and explains the steps victims must take in order to retrieve their data. The note states that the easiest path back to the company functioning normally is to pay the ransom.

Do not pay the ransom or negotiate with the threat actors. Contact SalvageData experts immediately to restore your files and local authorities to report the ransomware.

Sample of the Cuba ransomware ransom note:

How does Cuba ransomware infect a computer or network

Cuba ransomware is a dangerous malware that can infect a computer or network in several ways, including:

Spam and phishing emails that pretend to be legit businesses

Scammers send emails that appear to be from legitimate businesses, such as PayPal, UPS, FedEx, and others. These emails contain links or attachments that put your data and network at risk. One-click on a link or one download of an attachment can lock everyone out of your network.

Social engineering

It is a type of cyber attack that relies on human interaction to trick victims into divulging sensitive information, clicking on links or attachments, or taking other security-compromising actions. The goal of social engineering attacks is to exploit human psychology and behavior in order to gain access to sensitive information or systems. Attackers may impersonate a trusted authority figure, such as a bank representative or IT technician, or create a sense of urgency or fear in order to pressure the victim into taking action.

Zero-day attack

Refers to cybersecurity attacks that exploit a previously unknown vulnerability in software or hardware. These vulnerabilities are called “zero-day” because the developers of the software or hardware have had no time to patch the flaw or create a security update, leaving users without any protection.

Software vulnerability

This is a flaw in software code that can be exploited by attackers to compromise the security of a system. Vulnerabilities can occur at any stage of the software development life cycle, including design, coding, testing, and deployment.

How does Cuba ransomware work

Cuba ransomware is a type of malware that encrypts files on a victim’s computer and demands payment in exchange for the decryption key.

Here is how Cuba ransomware works:

1. Communication with command and control servers. Cuba ransomware communicates with command and control (C2) servers via SystemBC malware that uses SOCKS5 connections.
2. Scanning for available networks. Cuba ransomware scans connected and shared networks when “-netscan” is provided as an argument upon execution.
3. File encryption. Cuba ransomware encrypts personal files on the victim’s machine using a combination of symmetric and asymmetric encryption algorithms. Encrypted files are appended with a “.cuba” extension.
4. Data exfiltration. Refers to the unauthorized copying, transfer, or extraction of data from a system or network. Cuba threat actors exfiltrate sensitive information such as intellectual property, financial records, personally identifiable information (PII), or other types of data.
5. Drop off the ransom note. Cuba ransomware displays a ransom note, which explains what has happened and demands payment in exchange for the decryption key. Payment is typically demanded in Bitcoin or another cryptocurrency.
6. Double extortion. Like many modern ransomware variants, Cuba ransomware may also threaten to release stolen data if the victim does not pay the ransom.

If a victim does not have a backup of their encrypted files, they may feel that paying the ransom is the only way to recover their data. However, our experts advise against paying ransoms, as it may only encourage attackers to continue targeting victims with ransomware attacks and they may not give the decryption key.

How to handle a Cuba ransomware attack

The first step to recover from the Cuba ransomware attack is to isolate the infected computer by disconnecting it from the internet and removing any connected device. Then, you must contact local authorities. For US residents and businesses, it is the local FBI field office and the Internet Crime Complaint Centre (IC3).

To report a ransomware attack you must gather every information you can about it, including:

• Screenshots of the ransom note
• Communications with Cuba ransomware actors (if you have them)
• A sample of an encrypted file

However, if you prefer to contact ransomware removal and recovery professionals, then do nothing. Leave every infected machine the way it’s and call an emergency ransomware removal service. Restarting or shutting down the system may compromise the recovery service. Capturing the RAM of a live system may help get the encryption key, and catching a dropper file might be reverse-engineered and lead to the decryption of the data or understanding of how it operates.

You must not delete the ransomware, and keep every evidence of the attack. That’s important for digital forensics so experts can trace back to the hacker group and identify them. It is by using the data on your infected system that authorities can investigate the attack and find the responsible. A cyber attack investigation is not different from any other criminal investigation: it needs evidence to find the attackers.

1. Contact your Incident Response provider

A Cyber Incident Response is the process of responding to and managing a cybersecurity incident. An Incident Response Retainer is a service agreement with a cybersecurity provider that allows organizations to get external help with cybersecurity incidents. It provides organizations with a structured form of expertise and support through a security partner, enabling them to respond quickly and effectively in the event of a cyber incident.

An incident response retainer offers peace of mind to organizations, offering expert support before and in the aftermath of a cybersecurity incident. The specific nature and structure of an incident response retainer will vary according to the provider and the organization’s requirements. A good incident response retainer should be robust but flexible, providing proven services to enhance an organization’s long-term security posture.

If you contact your IR service provider, then they will take care of everything else. However, if you decide to remove the ransomware and recover the files with your IT team, then you can follow the next steps.

2. Identify the ransomware infection

This step should not be skipped since misidentification of the ransomware type can lead to incorrect and potentially harmful response strategies. For instance, attempting to remove the ransomware without proper knowledge could result in permanent data loss. Therefore, it’s crucial to correctly identify the malware that has infected a system before taking any action.

You can use any information you have at hand and input it into a ransomware ID tool. Then, you can look for a public decryption key. In the case of Cuba ransomware you can see the file extension .cuba at the end of your files name. This is one of its IOCs.

Indicators of Compromise (IOCs) are digital clues that cybersecurity professionals use to identify system compromises and malicious activities within a network or IT environment. Besides the file extension, Cuba ransomware has the capability to scan connected and shared networks when “-netscan” is provided as an argument. This allows it to spread more widely within an infected system.

3. Remove the ransomware and eliminate exploit kits

Before recovering your data, you must guarantee that your device is ransomware-free and that the attackers can’t make a new attack through exploit kits or other vulnerabilities. A ransomware removal service can delete the ransomware, create a forensics document for investigation, eliminate vulnerabilities, and recover your data.

Use anti-malware/anti-ransomware software to quarantine and remove the malicious software.

Important: By contacting ransomware removal services you can ensure that your machine and network have no trace of the Cuba ransomware. Also, these services can patch your system, preventing new attacks.

4. Use a backup to restore the data

Backups are the most efficient way to recover data. Make sure to keep daily or weekly backups, depending on your data usage. Then, no matter the disaster you can ensure you always will have your data.

5. Contact a ransomware recovery service

If you don’t have a backup or need help removing the ransomware and eliminating vulnerabilities, you should contact a data recovery service.

That’s because paying the ransom does not guarantee your data will be returned to you and it has great legal and ethical issues as well. The only guaranteed way you can restore every file and avoid financial and reputational losses is if you have a backup of it. If you don’t, ransomware data recovery services can help you decrypt and recover the files and protect your business from possible future attacks.

SalvageData experts can safely restore your files and prevent the Cuba ransomware from attacking your network again. Also, we offer a digital forensic report that you can use for further investigation and to understand how the cyber attack happened.

Prevent a Cuba ransomware attack

Preventing ransomware attacks is the best solution for data security since it’s easier and cheaper than recovering from them. Cuba ransomware can cost your business’s future and even close its doors.

These are a few tips to ensure you can avoid ransomware attacks:

• Utilize antivirus and anti-malware software
• Implement strong passwords
• Keep your software and operating system up to date
• Use firewalls for added protection
• Create a data recovery plan
• Regularly schedule backups to safeguard your data
• Be cautious of email attachments from unknown sources
• Avoid downloading files from suspicious websites
• Exercise caution when clicking on ads
• Only visit websites from reputable sources.