npm Software Supply Chain Attack Highlights New Risks

Ongoing npm Software Supply Chain Attack Exposes New Risks

September 17, 2025
By Sonatype Research Team

18 minute read time

Today, we've observed a software supply chain attack targeting npm maintainers' publishing credentials, followed by the rapid release of new versions carrying malicious payloads.

To be clear, this is not the same incident as the recent chalk/debug compromise. Nor is it confirmed to be the same actor as the similar, but distinct, event — S1ngularity — which occurred in late August 2025, when attackers stole an Nx project publishing token and pushed malicious versions of several Nx packages live on npm with the aim of exfiltrating sensitive data from users' systems over a short four-hour window.

Today's software supply chain attack concerns the Shai-Hulud campaign, which executes a multi-stage payload that steals credentials from the affected developer machine. If the payload achieves GitHub access, it then publishes the repository Shai-Hulud, which contains all exfiltrated secrets, and self-propagates by poisoning other npm packages in the project.

Sonatype, alongside other security research firms, has tracked this malicious campaign and continued to analyze indicators of compromise (IoCs). So far, collective efforts have tracked over 180 compromised packages.

Sonatype continues to track the affected packages, and our Release Integrity systems continue to discover newly affected items that we are adding to our data.

The Timeline So Far

Together, these incidents demonstrate a clear escalation in both scale and sophistication: from S1ngularity, which focused on a single compromised package, to the high-profile takeover of popular projects like chalk and debug, and now to a rapidly spreading campaign affecting more than 180 npm packages.

From Secrets to Spread: Technical Breakdown

The malware is engineered to both exfiltrate secrets and replicate itself across the ecosystem:

Why This Matters

Supply chain attacks of this kind highlight how fragile the global open source ecosystem can be when trusted distribution channels are compromised.

npm, as one of the world's largest package repositories, is at the heart of modern software development, meaning even a relatively small compromise can ripple across thousands of projects and organizations. Attacks like this are not isolated events, but part of a growing trend in which adversaries target the weakest links, credentials, developer accounts, or CI/CD pipelines, to maximize the impact of their campaigns.

The discovery that this variant is capable of self-propagation further elevates its significance. Unlike one-off malicious packages that need to be manually introduced, self-replicating malware accelerates the spread, making it far more difficult for developers and organizations to contain. Security researchers have warned that these worm-like traits represent an evolution in supply chain threats, raising the stakes for defenders.

What Wormable Malware Does

Wormable malware is dangerous because it doesn't stop at a single compromise. It actively seeks ways to expand. This infection follows a repeating, self-propagating cycle, powered in several areas by AI:

This self-reinforcing process allows the malware to spread quickly and widely, turning one compromised package into a chain reaction across the ecosystem.

A Full List of Vulnerable Packages and Versions

Written by Sonatype Research Team
Sonatype's Research Team is focused on bringing real-time, in-depth intelligence and actionable information about open source and third party vulnerabilities to Sonatype customers.

Tags: secure software supply chain, npm, security research, supply chain attacks, malicious code npm, Malware Analysis