registry  /  webpack-patch  /  1.1.9

webpack-patch@1.1.9

OSV Malicious Advisory

scanned 3h ago · by OpenSSF/OSV

OpenSSF/OSV advisory MAL-2026-5581 confirms this npm version as malicious. Package impersonates the webpack ecosystem but is unrelated to webpack. When the exported middleware is invoked, index.js spawns a detached `node lib/caller.js` child. caller.js fetches https://jsonkeeper.com/b/XRGF3 via axios and passes the response's `.cookie` field to `new Function.constructor('require', s)(require)`, executing attacker-controlled JavaScript with full Node privileges and a retry loop...

Advisory
MAL-2026-5581
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in webpack-patch (npm)
Details
Package impersonates the webpack ecosystem but is unrelated to webpack. When the exported middleware is invoked, index.js spawns a detached `node lib/caller.js` child. caller.js fetches https://jsonkeeper.com/b/XRGF3 via axios and passes the response's `.cookie` field to `new Function.constructor('require', s)(require)`, executing attacker-controlled JavaScript with full Node privileges and a retry loop. The C2 URL and HTTP header name/value are stored as base64 strings under sham `process.env` keys (`DEV_API_KEY` base64-decodes to `https://jsonkeeper.com/b/XRGF3`); a sibling const.js variant points at `https://jsonkeeper.com/b/4NAKK`, providing pivot URLs if the primary paste is removed. jsonkeeper.com is an anonymous mutable paste host — whoever controls the paste controls arbitrary code execution on every consumer that loads webpack-patch and exercises its API. The package.json description is generic boilerplate copied from an unrelated security policy, and the `main` is a fake pino-style middleware whose only meaningful effect is launching the dropper. ## Source: ghsa-malware (c0fa02eb8a58fb15c7b71d6ab94306801f07b0a14ff28abb18e83a5063fce9ea) 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.
Decision reason
OpenSSF Malicious Packages via OSV confirms webpack-patch@1.1.9 as malicious (MAL-2026-5581): Malicious code in webpack-patch (npm)

Source & flagged code

0 flagged
No flagged code excerpts are attached to this scan.

Findings

1 High
HighOsv Malicious Advisory