Which versions of esbuild-plugin-brotli are malicious?

The following npm versions of esbuild-plugin-brotli are flagged malicious: 0.2.1. Treat any of these as compromised.

How do I remediate esbuild-plugin-brotli if I installed it?

esbuild-plugin-brotli is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.

I already installed esbuild-plugin-brotli — how do I know if it already compromised me?

If esbuild-plugin-brotli 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 esbuild-plugin-brotli part of a known attack campaign?

Yes — esbuild-plugin-brotli is associated with the GHSA-jh24-3x78-mcqp 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 esbuild-plugin-brotli 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 esbuild-plugin-brotli (version 0.2.1). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging esbuild-plugin-brotli across your stack and pipelines.

Malicious package

esbuild-plugin-brotlinpm

Malicious code in esbuild-plugin-brotli (npm) Remove it immediately and rotate any exposed credentials.

MAL-2025-191087

Immediate action

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

npm uninstall esbuild-plugin-brotli

What this malware does

The package esbuild-plugin-brotli was found to contain malicious code.

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.

This package was compromised by the Sha1-Hulud: The Second Coming NPM worm. The malicious payload steals tokens and credentials and publishes them to GitHub. The worm will propogate itself to NPM packages the user owns and establish persistence is a GitHub action. The package may also destroy the user's home directory.

Malicious versions

1 flagged

0.2.1

Indicators of compromise (SHA-256)

37f724ce76d68fe05508decf7d5f7c1f06a3e8496f11ea51cc1acf1cce14815c

b3e1ab0d14aff5ad5f6422bf407955ba9b257748d558fb14ae728622c7bcdc34

3297dd1fa55908191d232d7ae6e086066d65d1676c5e1d50b624a84ba1083a11

Detection & response playbook

Credential / info stealer

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for esbuild-plugin-brotli (version 0.2.1). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging esbuild-plugin-brotli across your stack and pipelines.
If you installed it — respond
esbuild-plugin-brotli is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If esbuild-plugin-brotli 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 esbuild-plugin-brotli 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. esbuild-plugin-brotli on npm has been identified as a malicious package (version 0.2.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

GHSA-jh24-3x78-mcqp

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks esbuild-plugin-brotli-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Malware detection Runtime egress monitoring