# MAL-2026-17547: Malicious code in css-at-scope-polyfill (npm)


- **Type:** Malicious package
- **Package:** `css-at-scope-polyfill` (npm)
- **Published:** 5 Oct 2026

## What is MAL-2026-17547?

MAL-2026-17547 is a malicious package in css-at-scope-polyfill, published on 5 Oct 2026. 

### Official description

Package is published under a CSS-polyfill name but ships thunderboltRegistry.js, which exports Wix internal registry module names (thunderboltRegistry, siteAssetsRegistry, editorRegistry, corvidRegistry, etc.) so that a build resolving any of those names will load this file. On require(), an IIFE runs child_process.execSync to collect `id`, `whoami`, `uname`, `ifconfig`/`ip addr`, and the contents of /etc/hosts, plus a beacon containing node version, platform, pid, and hostname, and POSTs the output via fetch to the hardcoded HTTP endpoint http://dxpoc.gt.tc/callback.php/bb8968d0f67000433bf7005dd5ad2d1f. The payload clears any require.cache entries referencing 'thunderboltRegistry' and acquires child_process through three fallbacks, including instantiating a new Module via module.constructor to bypass mocks or sandboxes. The declared CSS-polyfill purpose has no relation to this behavior; the shape is a dependency-confusion squat against internal Wix modules.

## What should I do about MAL-2026-17547?

Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.

## Fix prompt for AI coding agents

```text
MAL-2026-17547 is a malicious package: css-at-scope-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-2026-17547/ (Markdown: https://insights.sbomify.com/MAL-2026-17547/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-17547

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-17547/
Summaries are generated and may contain mistakes; the official description above is the record.