eth-lib-utilsnpm
eth-lib-utils is a confirmed malicious npm package (MAL-2026-10499) that typosquats a legitimate package to trick installs (malicious versions 5.2.3, 5.2.4, 5.2.5). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in eth-lib-utils (npm)
What this malware does
Package [email protected] impersonates @ethereumjs/util / ethereumjs-util (README, author list, repository URL, and source tree copied from the legitimate package). The published Node build dist/index.js contains an unconditional require("assertcore") at module load that is absent from the TypeScript source src/index.ts and from the parallel dist.browser/index.js — the import was injected only into the shipped artifact. The required name assertcore is not declared in package.json; the declared dependency is the differently-named assertcoreutils (^2.3.2), an unrelated name shaped to look like an Ethereum companion package. The effect on a consumer that runs require('eth-lib-utils') in Node is to load whatever code is published under assertcore / assertcoreutils in the installer's process, while the package presents itself as a drop-in for a widely-used Ethereum utility. This is the standard typosquat-plus-transitive-dropper shape: the lure package looks like a clean re-export, the harmful code lives one resolution hop away in a name the installer never asked for.
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
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for eth-lib-utils (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging eth-lib-utils across your stack and pipelines.
If you installed it — respond
eth-lib-utils is a typosquat — you almost certainly intended a legitimately-named package. Remove eth-lib-utils, 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 eth-lib-utils 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 eth-lib-utils 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
Detect & block this
O3 blocks eth-lib-utils-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.