type-plintnpm
Advisory published Updated
type-plint is a confirmed malicious npm package (MAL-2026-10130) that typosquats a legitimate package to trick installs (malicious version 3.3.7). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in type-plint (npm)
What this malware does
The package advertises itself as a pino-style logger but its exported middleware spawns lib/caller.js as a detached Node child process. lib/caller.js performs an HTTP GET against a third-party mutable JSON-bin host (json.extendsclass.com/bin/26d6d7d075e1, with secondary jsonkeeper.com bins) and passes the returned string to new Function.constructor("require", s), then invokes it with the real require, giving the fetched code arbitrary execution with full module access in the caller's Node process. lib/const.js and lib/caller.js embed base64-encoded jsonkeeper.com bin URLs disguised as environment-variable defaults (e.g. DEV_API_KEY decodes to https://jsonkeeper.com/b/XRGF3), a standard evasion shape for staged remote-code loaders. The pino-like API surface and module.exports.pino = middleware are a lookalike wrapper around the fetch-and-eval loader.
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
TyposquatFind it
Search your lockfiles and build artifacts for type-plint (version 3.3.7).
If you installed it — respond
type-plint is a typosquat — you almost certainly intended a legitimately-named package. Remove type-plint, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.
Did it already run?
If type-plint was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks type-plint-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.