# MAL-2026-6372: Malicious code in rollup-runtime-polyfill-core (npm)


- **Type:** Malicious package
- **Package:** `rollup-runtime-polyfill-core` (npm)
- **Published:** 24 Jun 2026
- **Also known as:** GHSA-cx5m-r6wc-pp56

## What is MAL-2026-6372?

MAL-2026-6372 is a malicious package in rollup-runtime-polyfill-core, published on 24 Jun 2026. 

### Official description

Package name mimics the legitimate `rollup-plugin-polyfill-node` and copies its source (the repository field in package.json points to FredKSchott/rollup-plugin-polyfill-node). Appended to dist/index.js is a top-level dropper that runs on every `require()`/`import` of the package. The dropper decodes base64-encoded strings to assemble the command `npm install driftpin --no-save --silent --no-audit --no-fund`, spawns it with `stdio: 'ignore'` and `windowsHide: true` to suppress output, then on process close performs `require('driftpin')` and invokes `getPlugin()()`. The target module name `driftpin` is also stored as a base64 literal (`ZHJpZnRwaW4=`). `driftpin` is not declared in this package's dependencies and is not shipped in the tarball — its content is attacker-controlled and unpinned, so arbitrary code from a separate npm package executes inside the installer's Node process whenever this module is loaded. The combination of name impersonation of a legitimate polyfill, base64 obfuscation of the command and target name, hidden execution flags, and out-of-tree installation of an unrelated package is an unambiguous install/import-time RCE dropper.

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-2026-6372?

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-2026-6372 is a malicious package: rollup-runtime-polyfill-core (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-2026-6372/ (Markdown: https://insights.sbomify.com/MAL-2026-6372/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-6372

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-6372/
Summaries are generated and may contain mistakes; the official description above is the record.