NOOSE ransomware is a variant of the Chaos ransomware family. Like other ransomware, NOOSE encrypts files on infected computers, making them inaccessible to users. In this guide, you can learn how the Noose ransomware spreads and infects devices, how to take proactive prevention measures, and what to do in case of a successful attack.

SalvageData experts recommend proactive data security measures, such as regular backups, strong cybersecurity practices, and keeping software up to date, to protect against malware attacks. And, in case of a cyber attack, contact our malware recovery experts immediately.

What is NOOSE ransomware

NOOSE is a new ransomware variant based on the Chaos ransomware, and poses significant risks to individuals and businesses. It appends the ".NOOSE" extension to encrypted files and changes the desktop wallpaper. It was first reported by PCrisk in late January 2024, on X.Additionally, NOOSE creates a ransom note named "OPEN_ME.txt," which instructs victims on how to pay a ransom, usually demanded in the form of Monero cryptocurrency, to receive decryption software. The ransom note often includes threats and promises of decryption upon payment verification. The ransomware spreads through various methods, including infected email attachments, malicious websites, and pirated software. This is why it’s so important to employ prevention measures such as updating software, avoiding suspicious links and attachments, and maintaining backups of important data.

Everything we know about NOOSE ransomware

Confirmed Name

• NOOSE virus

NOOSE ransomware decryptor

• As of this article's publication, there’s no public NOOSE ransomware decryptor.

Threat Type

• Ransomware
• Crypto virus
• Files locker
• Data leak

Encryption file extension

• .NOOSE

Ransom note file name

• OPEN_ME.txt

Detection names

• Avast Win32:RansomX-gen [Ransom]
• Emsisoft Generic.Ransom.HydraCrypt.79E3A884 (B)
• Kaspersky HEUR:Trojan-Ransom.MSIL.Agent.gen
• Malwarebytes Generic.Malware.AI.DDS
• Microsoft Ransom:MSIL/FileCoder.AD!MTB
• Sophos Troj/Ransom-GWT

Distribution methods

• Phishing emails
• Exploit kits
• Peer-to-peer networks
• Trojans
• Fake software updaters

NOOSE ransomware methods of infection and execution

NOOSE ransomware is a dangerous cyber threat that exploits systems and machine vulnerabilities to gain access and spread across the network. Here is a breakdown of how it works.

Initial access

NOOSE ransomware gains initial access to a system through various means, such as infected email attachments containing malicious payloads or links. It also exploits vulnerabilities in unpatched software or operating systems.This ransomware is also known to use social engineering, which is a technique that tricks users into downloading and executing the malware. An example of social engineering is Phishing email attacks that also deceive victims as the threat actor impersonates legitimate businesses.

Lateral movement

Once inside a system, NOOSE ransomware will attempt to move laterally across the network to infect other devices or systems connected to the same network. To do so, it exploits vulnerabilities within the network protocols or weak security configurations.

Data encryption

The NOOSE ransomware encrypts files on the infected device using strong encryption algorithms to lock files, appending the ".NOOSE" files extension to indicate they are inaccessible to the user.

Ransom note drop-off

Upon completing the encryption process, NOOSE ransomware drops a ransom note typically named "OPEN_ME.txt" on the victim's desktop and in folders containing encrypted files. It also changes the desktop wallpaper.The ransom note contains instructions from the attackers, detailing how the victim can pay a ransom (usually in cryptocurrency like Monero) to receive a decryption key.

Do not pay the ransom! Contacting a ransomware recovery service can restore your files and remove any potential threat.

NOOSE ransomware Indicators of Compromise (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.They are essentially digital versions of evidence left at a crime scene, and potential IOCs include unusual network traffic, privileged user logins from foreign countries, strange DNS requests, system file changes, and more. When an IOC is detected, security teams evaluate possible threats or validate its authenticity. IOCs also provide evidence of what an attacker had access to if they did infiltrate the network.

NOOSE ransomware-specific IOC

• File Extensions: .NOOSE
• Ransom Note Filename: OPEN_ME.txt
• Cyber Criminal Contact: malignant@tuta[.]io

How to handle a NOOSE ransomware attack

The first step to recovering from a NOOSE 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 FBI and the Internet Crime Complaint Centre (IC3).To report a malware attack you must gather every information you can about it, including:

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

However, if you prefer to contact professionals, then it’s best to leave every infected machine the way it is and ask for an emergency ransomware removal service. These professionals are equipped to quickly mitigate the damage, gather evidence, potentially reverse the encryption, and restore the system.

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, i.e. file executing the malicious payload, might be reverse-engineered and lead to decryption of the data or understanding how it operates.You must not delete the ransomware, and keep every evidence of the attack. That’s important for digital forensics experts to 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. 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 during 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. An incident response retainer's specific nature and structure 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, they can take over immediately and guide you through every step in the ransomware recovery. However, if you decide to remove the malware yourself and recover the files with your IT team, then you can follow the next steps.

2. Use a backup to restore the data

The importance of backup for data recovery cannot be overstated, especially in the context of various potential risks and threats to data integrity. Backups are a critical component of a comprehensive data protection strategy. They provide a means to recover from a variety of threats, ensuring the continuity of operations and preserving valuable information. In the face of ransomware attacks, where malicious software encrypts your data and demands payment for its release, having a backup allows you to restore your information without succumbing to the attacker's demands.Make sure to regularly test and update your backup procedures to enhance their effectiveness in safeguarding against potential data loss scenarios. There are several ways to make a backup, so you must choose the right backup medium and have at least one copy of your data stored offsite and offline.

3. Contact a malware recovery service

If you don’t have a backup or need help removing the malware and eliminating vulnerabilities, contact a data recovery service. Paying the ransom does not guarantee your data will be returned to you. The only guaranteed way to restore every file is if you have a backup. If you don’t, ransomware data recovery services can help you decrypt and recover the files.SalvageData experts can safely restore your files and prevent NOOSE ransomware from attacking your network again, contact our recovery experts 24/7.

Prevent the NOOSE ransomware attack

Preventing malware is the best solution for data security. is easier and cheaper than recovering from them. NOOSE Ransomware can cost your business’s future and even close its doors. These are a few tips to ensure you can avoid malware attacks:

• Keep your operating system and software up-to-date with the latest security patches and updates. This can help prevent vulnerabilities that can be exploited by attackers.
• Use strong and unique passwords for all accounts and enable two-factor authentication whenever possible. This can help prevent attackers from gaining access to your accounts.
• Be cautious of suspicious emails, links, and attachments. Do not open emails or click on links or attachments from unknown or suspicious sources.
• Use reputable antivirus and anti-malware software and keep it up-to-date. This can help detect and remove malware before it can cause damage.
• Use a firewall to block unauthorized access to your network and systems.
• Network segmentation to divide a larger network into smaller sub-networks with limited interconnectivity between them. It restricts attacker lateral movement and prevents unauthorized users from accessing the organization’s intellectual property and data.
• Limit user privileges to prevent attackers from gaining access to sensitive data and systems.
• Educate employees and staff on how to recognize and avoid phishing emails and other social engineering attacks.