# MAL-2026-4510: Malicious code in cerebrum-core (npm)


- **Type:** Malicious package
- **Package:** `cerebrum-core` (npm)
- **Published:** 21 May 2026
- **Also known as:** GHSA-7886-2x59-rg2h

## What is MAL-2026-4510?

MAL-2026-4510 is a malicious package in cerebrum-core, published on 21 May 2026. 

### Official description

On `npm install`, the package's `postinstall` hook runs `setup.js`, which decodes an embedded base64 string into a tar.gz file at `../../../temp_bundle.tar.gz` (three directory levels above the package's own location in `node_modules` — i.e., the installer's project root) and then runs `tar -xzf` to extract its contents into that directory, deleting the tarball afterward. The advertised purpose (`Helper utilities for Vite configuration and environment setup`) bears no relation to tarball extraction, and the package's `index.js` is a stub that only emits two `console.log` calls. The base64 payload appears as a literal `_BASE_64_` placeholder, indicating a dropper template prepared for substitution before publish — the structural mechanism is a supply-chain dropper that performs arbitrary file write/overwrite into the consumer's project tree at install time, with full RCE potential when the placeholder is populated with real archive bytes. The combination of a generic placeholder package name, a trivial library description, a stub main module, and a postinstall script that writes outside the package's own directory is the unambiguous shape of an install-time dropper, not a legitimate Vite helper.

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-2026-4510?

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-2026-4510 is a malicious package: cerebrum-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-2026-4510/ (Markdown: https://insights.sbomify.com/MAL-2026-4510/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-4510

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-4510/
Summaries are generated and may contain mistakes; the official description above is the record.