Which versions of llm-nebula are malicious?

The following npm versions of llm-nebula are flagged malicious: 1.0.0. Treat any of these as compromised.

How do I remediate llm-nebula if I installed it?

Remove llm-nebula from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.

I already installed llm-nebula — how do I know if it already compromised me?

If llm-nebula was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.

Is llm-nebula part of a known attack campaign?

Yes — llm-nebula is associated with the IN-MAL-2026-020610, GHSA-w7wp-5j6j-rgg5 campaign. Packages in the same campaign often share infrastructure and payloads, so check whether any related packages are also in your dependency tree.

How do I find llm-nebula across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for llm-nebula (version 1.0.0).

Malicious package

llm-nebulanpm

Advisory published Sep 28, 2026Updated Oct 12, 2026

llm-nebula is a confirmed malicious npm package (MAL-2026-17230) that executes malicious code on install (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in llm-nebula (npm)

MAL-2026-17230

Immediate action

Remove the package, then rotate any secrets the build/runtime could reach.

npm uninstall llm-nebula

What this malware does

Package presents itself as an LLM SDK (nebula.js exposes a small client stub) but declares preinstall: node preinstall.cjs in package.json, and preinstall.cjs is a ~232KB single-line obfuscated blob that runs automatically on npm install. The script wraps its body in a Function(...) constructor and uses a custom PRNG-based string decoder (TEA/xorshift-style constants 0x9e3779b9 / 0x243f6a88 / 0x6a09e667) over a packed printable-ASCII string plus a hex-int array to reconstruct characters via String.fromCharCode, driving a control-flow-flattened switch dispatcher. Node builtins and method names are resolved dynamically at runtime (e.g. Ooa8zU["Bd5Wj1"]("fs")) so module ids, filesystem paths, network destinations, and command strings are not visible without executing the decoder. This obfuscation-plus-lifecycle-hook composition is the canonical install-time dropper / RCE shape: the benign-looking library entry serves as a cover story while the hidden preinstall payload runs on any consumer's machine at install time with the user's privileges, capable of arbitrary filesystem, process, and network operations.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

0eee293a9973027154eea71635c14e8a4cb2ad8a1e4f80a65399ad874afcb669

74d490ae52177b63247dc6045ff7bdefecafe59a9fee080c7e30baa247245339

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for llm-nebula (version 1.0.0).
If you installed it — respond
Remove llm-nebula from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If llm-nebula was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.

Frequently asked questions

No. llm-nebula on npm has been identified as a malicious package (version 1.0.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-020610GHSA-w7wp-5j6j-rgg5

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks llm-nebula-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.

Malware detection Runtime egress monitoring

Explore

All malware advisories How O3 detects malware Vulnerability database