NodeSnake RAT: Interlock Ransomware Invests Heavily in Custom Tooling

Researchers’ recent investigation into two newly discovered variants of the NodeSnake Remote Access Trojan (RAT) provides compelling evidence that the Interlock ransomware group is heavily invested in developing custom tooling to enhance stealth, flexibility, and effectiveness across its operations.  

NodeSnake, written in Node.js, is a bespoke RAT with no known public codebase or reuse, and demonstrates an intentional strategy by Interlock to evade detection by traditional antivirus and endpoint protection systems, HackRead reports.

By avoiding commodity malware and building its own tools, Interlock ensures that its payloads bypass signature-based detection methods and behavioral heuristics commonly used by EDR and XDR platforms. The use of less common programming languages like Node.js further reduces the likelihood of triggering existing detection rules.  

Both NodeSnake variants uncovered in this research exhibit clear signs of active development and operational tailoring, including live debugging capabilities, custom obfuscation techniques, and stealthy communication using Cloudflare Tunnel for command-and-control (C2), a tactic that blends malicious traffic with legitimate services to avoid raising red flags.

Perhaps most notably, NodeSnake’s modular design allows the malware to dynamically adapt to the target environment. This modularity means Interlock operators can adjust the payload functionality—such as persistence mechanisms, data collection modules, or lateral movement tools—based on the specific infrastructure, defenses, and value of the victim.  

Such flexibility not only increases operational success rates but also enables more surgical targeting and long-term access within sensitive environments like higher education and government networks.

Researchers’ findings strongly suggest that NodeSnake is just one component in a broader, customized offensive toolkit maintained by Interlock. This approach underscores the growing trend among ransomware operators to shift from off-the-shelf tools to tailored malware ecosystems built for evasion, precision, and control—further blurring the line between financially motivated cybercrime and advanced persistent threat tradecraft.

Takeaway: If you’re in the sights of a crew like Interlock (or Scattered Spider), understand this: these aren’t smash-and-grab crews, they’re disciplined operators running highly structured campaigns.  

They’re investing real time and financial resources into custom tooling like NodeSnake, for bespoke loaders, for Cloudflare tunneling, on EDR killers—because they expect a serious return.  

Just like any business, they don't build what they can't monetize. And the return they’re banking on? Massive ransom payouts from targets handpicked for their ability to pay. These aren’t commodity payloads, they’re modular, stealthy tools designed to fit your environment like a key in a lock. That’s what makes them dangerous.

So how do you fight back? Raise the bar. Every best practice you implement like tight network segmentation, strict least privilege access, hard MFA policies, airtight application controls and more, burns their time and blows their ROI.

These aren’t just check-the-box controls; they’re friction. And for attackers, friction equals cost. The more effort it takes to move laterally, escalate privileges, or maintain access, the less appealing of a target your organization becomes. You're not just defending; you’re degrading the economics calculation of the entire operation.

Force them to rethink their potential financial costs. Because every failed op, every busted intrusion, eats into the resources they’d use to build their next tool. No profit, no reinvestment. That’s one of the ways you can help break this model.

Halcyon eliminates the business impact of ransomware. Modern enterprises rely on Halcyon to prevent ransomware attacks, eradicating cybercriminals’ ability to encrypt systems, steal data, and extort companies – talk to a Halcyon expert today to find out more, and check out our quarterly RaaS and extortion group reference guide, Power Rankings: Ransomware Malicious Quartile.