fastify-client-bundler (npm) · Malicious Code
Affects fastify-client-bundlerSource GCVE Database
Malicious package : remove fastify-client-bundler and rotate any secrets on hosts that installed it.
Data as of 26 Oct 2026, 16:15 UTC
Malicious package
Published to npm · OSV MAL-2026-12379
What to do
Remove fastify-client-bundler from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| npmfastify-client-bundler | Affected
| Fixed in– |
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Description
The npm package fastify-client-bundler version 1.4.0 contains malicious code that fetches and executes remote code from a hardcoded IP address. This remote code execution occurs via a function that compiles and runs JavaScript obtained from the endpoint, enabling arbitrary code execution in the Node.js process. The package's declared functionality is a decoy, while the actual behavior includes loading dependencies consistent with a Windows credential and wallet stealer. No official patch or remediation information is provided, and no known exploits in the wild have been reported.