OpenSSF/OSV advisory MAL-2026-6325 confirms this npm version as malicious. Package name and metadata impersonate the legitimate @ethereumjs/util / ethereumjs-util packages: README is copied verbatim from the upstream ethereumjs project (and even instructs users to `npm install eth-util`), the contributor list and repository URL point at ethereumjs/ethereumjs-monorepo, but the package is published under a different name and ownership. The published dist/index.js (line ~57) contains...
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in web3-eth-util (npm)
Details
Package name and metadata impersonate the legitimate @ethereumjs/util / ethereumjs-util packages: README is copied verbatim from the upstream ethereumjs project (and even instructs users to `npm install eth-util`), the contributor list and repository URL point at ethereumjs/ethereumjs-monorepo, but the package is published under a different name and ownership. The published dist/index.js (line ~57) contains `require("assertcore")` and package.json declares `"assertcore": "^3.1.7"` as a runtime dependency. The human-authored src/index.ts has no such import, and the browser build at dist.browser/index.js also omits it — the extra require is injected only into the Node-targeted build that ships in the npm tarball, so reviewers reading the GitHub source see clean code while `npm install` + `require('web3-eth-util')` silently loads the third-party 'assertcore' package in the consumer's Node process with full privileges. 'assertcore' is not part of the legitimate @ethereumjs/util sources and resembles a typosquat of the standard 'assert' module. The combination — brand impersonation of a widely used Ethereum utility package, source/dist divergence hiding the injection from GitHub readers, and a require-time pull of an unrelated third-party package — is a dependency-chain dropper pattern that delivers attacker-controlled code to anyone who installs and imports this package.
Decision reason
OpenSSF Malicious Packages via OSV confirms web3-eth-util@6.2.8 as malicious (MAL-2026-6325): Malicious code in web3-eth-util (npm)