Summary:
Symantec has uncovered a new ransomware operation, dubbed Nitrogen, which has been notably active over the past four months. This group has targeted a wide range of industries, including construction, financial services, manufacturing, and technology. The majority of Nitrogen's victims are located in the USA, Canada, and the UK, with the USA accounting for over 50% of the incidents in recent months.

Similar to other ransomware groups, Nitrogen employs double extortion tactics. In addition to encrypting files, the group also exfiltrates sensitive data and threatens to release it on their Tor-based data leak site if the ransom is not paid. Files encrypted by Nitrogen are typically appended with the .NBA extension. After a successful encryption, the attackers leave behind a ransom note, which provides instructions on how victims can contact the group and negotiate the ransom payment.

“To initiate negotiations, the victim is instructed to use the Tor Browser or qTox app to contact the group through specified channels. The attackers promise a decryption tool, proof of data deletion, and security recommendations upon payment, portraying themselves as professional and in control while using fear and urgency to manipulate the victim into compliance,” note researchers.

Security Officer Comments:
Nitrogen typically gains initial access by employing malicious ads on search engines like Google and Bing. These ads lead victims to fraudulent websites offering fake software downloads for legitimate applications, such as AnyDesk, Cisco AnyConnect, and WinSCP. When victims download the software, they inadvertently deploy the Nitrogen ransomware, which then proceeds to encrypt files on the compromised system.

One notable feature of Nitrogen ransomware is its use of anti-analysis techniques to bypass security defenses. These include debugger detection, virtual machine detection, and code obfuscation—such as the use of stack strings—to complicate reverse engineering efforts. Additionally, the ransomware has the ability to conduct system discovery, enumerating PE sections and gathering crucial system information, allowing the attackers to target more valuable and sensitive systems within the victim’s network.

Suggested Corrections:
Backup your data, system images, and configurations, regularly test them, and keep the backups offline: Ensure that backups are regularly tested and that they are not connected to the business network, as many ransomware variants try to find and encrypt or delete accessible backups. Maintaining current backups offline is critical because if your network data is encrypted with ransomware, your organization can restore systems.

Update and patch systems promptly: This includes maintaining the security of operating systems, applications, and firmware in a timely manner. Consider using a centralized patch management system; use a risk-based assessment strategy to drive your patch management program.

Test your incident response plan: There's nothing that shows the gaps in plans more than testing them. Run through some core questions and use those to build an incident response plan: Are you able to sustain business operations without access to certain systems? For how long? Would you turn off your manufacturing operations if business systems such as billing were offline?

Check Your Security Team's Work: Use a 3rd party pen tester to test the security of your systems and your ability to defend against a sophisticated attack. Many ransomware criminals are aggressive and sophisticated and will find the equivalent of unlocked doors.

Segment your networks: There's been a recent shift in ransomware attacks – from stealing data to disrupting operations. It's critically important that your corporate business functions and manufacturing/production operations are separated and that you carefully filter and limit internet access to operational networks, identify links between these networks, and develop workarounds or manual controls to ensure ICS networks can be isolated and continue operating if your corporate network is compromised. Regularly test contingency plans such as manual controls so that safety-critical functions can be maintained during a cyber incident.

Train employees:
Email remains the most vulnerable attack vector for organizations. Users should be trained on how to avoid and spot phishing emails. Multi-factor authentication can help prevent malicious access to sensitive services.

Link(s):
https://www.broadcom.com/support/security-center/protection-bulletin/nitrogen-ransomware