MalwarePublished 25 Jul 2026Updated 11 Aug 2026

whs4_deu (npm) · Malicious Code

Affects whs4_deuSource GCVE Database

Malicious package : remove whs4_deu and rotate any secrets on hosts that installed it.

Data as of 11 Aug 2026, 18:56 UTC

Classification

Malicious package

Published to npm · OSV MAL-2026-11070

What to do

Remove whs4_deu 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
npmwhs4_deu	Affected =1.0.1 =1.0.0	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

Description

The npm package 'whs4_deu' versions 1.0.0 and 1.0.1 contains malicious code that executes during installation. Specifically, a postinstall script runs a JavaScript file that sends the installer's absolute file path, Node.js version, and platform details to a hardcoded Discord webhook. This behavior is undocumented and the webhook URL is obfuscated to evade detection. The package provides no legitimate functionality and is flagged as malicious due to its communication with a domain linked to malicious activity.

Impact

The malicious postinstall script can leak sensitive environment information including the installer's file path, potentially exposing usernames and directory layouts, as well as Node.js version and platform details. This data exfiltration to a hardcoded external webhook can aid attackers in reconnaissance or further targeted attacks. There is no indication of direct code execution beyond the postinstall script or broader system compromise from the provided data.

Defensive guidance

Users should avoid installing the 'whs4_deu' package versions 1.0.0 and 1.0.1. Monitor package sources and dependency trees to prevent inadvertent installation. Check vendor advisories or npm security advisories for updates or removal notices regarding this package.

Summary

The 'whs4_deu' npm package versions 1.0.0 and 1.0.1 include a postinstall hook that executes 'index.js' upon installation. This script collects sensitive environment information such as the absolute filename path (which can reveal OS username and directory structure), Node.js version, and system architecture, then sends this data to a hardcoded Discord webhook URL. The webhook URL is split in the code to avoid simple detection by string searches. The package does not offer any functionality consistent with its name, and its sole observable behavior is this install-time data beaconing. The OpenSSF Package Analysis project and Amazon Inspector have identified this package as malicious due to its unauthorized data exfiltration and communication with a suspicious domain.

References

Community reviews

Loading reviews…

What to do

Affected software

Description

AI analysisMachine-generated, updated 11 Aug 2026, 18:56 UTC

Technical details

References

Community reviews