Which versions of fastify-client-bundler are malicious?

The following npm versions of fastify-client-bundler are flagged malicious: 1.4.0. Treat any of these as compromised.

How do I remediate fastify-client-bundler if I installed it?

fastify-client-bundler 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 fastify-client-bundler — how do I know if it already compromised me?

If fastify-client-bundler 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 fastify-client-bundler part of a known attack campaign?

Yes — fastify-client-bundler is associated with the IN-MAL-2026-014854 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 fastify-client-bundler 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 fastify-client-bundler (version 1.4.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging fastify-client-bundler across your stack and pipelines.

Malicious package

fastify-client-bundlernpm

fastify-client-bundler is a confirmed malicious npm package (MAL-2026-12379) that steals credentials and exfiltrates sensitive data (malicious version 1.4.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in fastify-client-bundler (npm)

MAL-2026-12379

Immediate action

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

npm uninstall fastify-client-bundler

What this malware does

index.js (the package main) defines a getPlugin() function that fetches JSON from a hardcoded bare-IP HTTPS endpoint at 31.97.137.157:45000 and compiles the response's credits field via new Function(...) with require, module, exports, process, Buffer, and Promise injected, then invokes it — granting the remote endpoint arbitrary code execution in the Node process that loads the package. The package's declared purpose (a Fastify client bundler / Tailwindcss forms bundler) and CDN-style helpers (setDefaultModule constructing cdnjs URLs) are unused decoys; the actually-invoked network path targets the bare IP. Bundled runtime dependencies (@primno/dpapi, better-sqlite3, node-machine-id) are consistent with a Windows credential/wallet stealer that a delivered payload would load through the injected require.

Malicious versions

1 flagged

1.4.0

Indicators of compromise (SHA-256)

370379b65a0c7e31b5bf43362a0c1fa1312f9a458a7af9a4a3d95892dc2a6935

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 fastify-client-bundler (version 1.4.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging fastify-client-bundler across your stack and pipelines.
If you installed it — respond
fastify-client-bundler 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 fastify-client-bundler 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 fastify-client-bundler 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. fastify-client-bundler on npm has been identified as a malicious package (version 1.4.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-014854

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks fastify-client-bundler-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

Explore

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