MAL-2026-3719 Malicious code in web3-core-js (npm)
- Package
- web3-core-js
- Registry
- npm
What is MAL-2026-3719?
MAL-2026-3719 is a malicious package in web3-core-js, published on 13 May 2026.
Official description
package.json declares a lifecycle hook that invokes require('child_process') and execSync with a curl command at install time. This pattern fetches remote content and executes it on the installer's machine as part of npm install, before any user code runs. The package name mimics the widely-used web3/web3-core ecosystem while shipping only a lifecycle trigger for remote execution — no library code consistent with the claimed web3 purpose is present. Running npm install web3-core-js on any developer or CI machine results in arbitrary attacker-controlled bytes being fetched and executed with the privileges of the installing user.
The OpenSSF Package Analysis project identified 'web3-core-js' @ 2.0.0 (npm) as malicious.
It is considered malicious because:
- The package executes one or more commands associated with malicious behavior.
What should I do about MAL-2026-3719?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.