fastify-bundlernpm
fastify-bundler is a confirmed malicious npm package (MAL-2026-10520) that steals credentials and exfiltrates sensitive data (malicious versions 1.4.13, 1.4.14, 1.4.15…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in fastify-bundler (npm)
What this malware does
The package's exported getPlugin function fetches JSON from https://svganchordev.net/icons/105 and passes the response's data.credits field to new Function() with require, module, process, Buffer, and other Node globals bound, then invokes it. Any consumer that imports fastify-bundler and calls the advertised API executes attacker-supplied JavaScript with full Node privileges; the remote operator can change the payload at any time. The package's declared dependencies (@primno/dpapi for Windows DPAPI credential decryption, better-sqlite3/sqlite3 for Chromium Login Data and Cookies stores, node-machine-id for host fingerprinting, socket.io-client, axios, request) are injected into the require() available to the remote payload, providing a ready-made toolkit for browser-credential theft and C2. The package identity is also deceptive: it is published as 'fastify-bundler' with a description claiming to be a 'high-performance web framework for Node.js', while the shipped README is titled 'Tailwindcss Forms Bundler' and instructs users to `npm install tailwindcss-forms-bundle' — a name/README mismatch targeting three unrelated popular ecosystems to attract installs.
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
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for fastify-bundler (4 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging fastify-bundler across your stack and pipelines.
If you installed it — respond
fastify-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-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-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
Campaign
References
Credits
- Amazon Inspector · finder
- ReversingLabs · finder
Detect & block this
O3 blocks fastify-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.