Which versions of commonjs-assertion are malicious?

The following npm versions of commonjs-assertion are flagged malicious: 1.2.7. Treat any of these as compromised.

How do I remediate commonjs-assertion if I installed it?

Remove commonjs-assertion 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 commonjs-assertion — how do I know if it already compromised me?

If commonjs-assertion was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.

Is commonjs-assertion part of a known attack campaign?

Yes — commonjs-assertion is associated with the GHSA-mfjj-4625-mpvr, IN-MAL-2026-017282 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 commonjs-assertion across my projects, lockfiles, and CI pipelines?

Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for commonjs-assertion (version 1.2.7). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging commonjs-assertion across your stack and pipelines.

Malicious package

commonjs-assertionnpm

commonjs-assertion is a confirmed malicious npm package (MAL-2026-13719) that executes malicious code on install (malicious version 1.2.7). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in commonjs-assertion (npm)

MAL-2026-13719

Immediate action

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

npm uninstall commonjs-assertion

What this malware does

Package presents itself as a chai-like assertion library. index.js uses hex-encoded strings to hide the identifiers 'child_process' and 'node' and, on require, unconditionally invokes child_process.spawn to launch a detached, stdio-ignored node child running lib/chai/utils/assertion.js. That file is a heavily obfuscated loader (obfuscator.io rotated string array plus a custom base64/URI decoder) whose decoded logic performs an HTTP GET to a URL reconstructed from the encoded string array and passes the response body to new Function(..., body)(require), granting the fetched remote code full Node access. The assertion.js file is not referenced by chai's real code and is only reachable via the hex-hidden spawn in index.js. Importing the package causes remote code execution on the installer's host at load time.

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

1.2.7

Indicators of compromise (SHA-256)

0d9cb8e89c50d78130775904af2df0dc68d2fa17454fcd0c042e273c51e40855

29c3fd028dc7e2493e59a3f81bb26702030dac0a64a42d845bd23ea116352f94

Detection & response playbook

Malicious package

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for commonjs-assertion (version 1.2.7). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging commonjs-assertion across your stack and pipelines.
If you installed it — respond
Remove commonjs-assertion 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 commonjs-assertion was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks commonjs-assertion before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.

Frequently asked questions

No. commonjs-assertion on npm has been identified as a malicious package (version 1.2.7 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

GHSA-mfjj-4625-mpvrIN-MAL-2026-017282

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks commonjs-assertion-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

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