MAL-2026-17556 Malicious code in css-ogojwh-polyfill (npm)
Malicious package
Published
MAL-2026-17556 is a malicious package: css-ogojwh-polyfill (npm). Every version was published to cause harm.
Task:
1. Search this repository's dependency manifests and lockfiles for the package, including transitive dependencies.
2. If it is present, remove it, regenerate the lockfile with the project's package manager, and replace whatever it was used for.
3. List any CI runners, developer machines or containers that installed it, so their secrets can be rotated.
4. If the package is not used anywhere, say so and change nothing.
Reference: https://insights.sbomify.com/MAL-2026-17556/ (Markdown: https://insights.sbomify.com/MAL-2026-17556/index.md)
- Package
- css-ogojwh-polyfill
- Registry
- npm
What is MAL-2026-17556?
MAL-2026-17556 is a malicious package in css-ogojwh-polyfill, published on 5 Oct 2026.
Official description
[email protected] presents itself as a CSS polyfill but ships thunderboltRegistry.js which, on require, runs an IIFE that executes shell commands via child_process.execSync (id, whoami, uname -a, ifconfig/ip addr, cat /etc/hosts) and POSTs their output along with hostname, Node version, platform and pid to the hardcoded endpoint http://dxpoc.gt.tc/callback.php/bb8968d0f67000433bf7005dd5ad2d1f, with a beacon label of
rce-poc. The module also exports no-op Proxy stubs under module names matching Wix thunderbolt registry modules (thunderboltRegistry, siteAssetsRegistry, editorRegistry), consistent with a dependency-confusion / typosquat shim whose only real behavior is the recon-and-exfil payload executed at import time.What should I do about MAL-2026-17556?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.