NPM · AUGUST 2026 · CONFIRMED

Npm Supply Chain Attack: ChainDrop Worm Compromises Packages

Severity
HIGH
Affected component
npm packages (npm)
Patched version
Not yet available

A self-propagating worm has published compromised versions of dozens of npm packages using stolen maintainer credentials. Check the list of affected packages and update to the latest secure versions.

What happened

A self-propagating worm has compromised dozens of npm packages using stolen maintainer credentials. The worm, known as ChainDrop, has published malicious versions of popular packages in the keyv and Cacheable namespaces. These compromised packages have been downloaded by unsuspecting developers, potentially leading to the execution of malicious code on their systems.

The attack leverages lifecycle hooks like preinstall or postinstall to trigger the execution of malicious code. In some cases, the packages come with a README that instructs developers to load them with require(), a built-in function to import modules, local files, and third-party packages. This leads to the execution of a downloader that fetches a compatible payload from one of several Cloudflare Workers hosts.

The payloads vary depending on the host operating system and processor architecture. For example, Linux x64 systems receive a payload from sdk.dl.wel1[.]ru, while Windows systems receive a payload from net.dl.wel1[.]ru. If the HTTPS-based downloads fail, the malware switches to a platform-specific domain and uses DNS TXT records to obtain the next-stage from the domain wel1[.]ru.

What to do about it

How 0Day would have caught this

MATCHED TO YOUR ACTUAL DEPENDENCY GRAPH0Day matches every incoming threat signal against your GitHub organization’s full dependency graph, including transitive dependencies. If npm packages is anywhere in your dependency tree, the engineers who own the affected repositories get a push alert the moment it is flagged — no manual audit to remember to run.

Read how this differs from waiting on a scanner to catch a known advisory, or see the exact, read-only access 0Day needs to do this for an organization.

Frequently asked questions

Am I affected?

If you are using any of the compromised npm packages, you may be affected. Check the list of affected packages and update to the latest secure versions.

What should I do right now?

Check the list of affected packages and update to the latest secure versions. Monitor your systems for any unusual activity or unauthorized access.

How did this attack happen?

The attack leveraged stolen maintainer credentials to publish compromised versions of popular npm packages. The malicious packages used lifecycle hooks to execute malicious code upon installation.

What are the potential impacts of this attack?

The potential impacts include unauthorized access to systems, data theft, and the execution of malicious code on affected systems.

Sources

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