# MAL-2026-13821: Malicious code in mnchfnvbue1 (npm)


- **Type:** Malicious package
- **Package:** `mnchfnvbue1` (npm)
- **Published:** 12 Aug 2026
- **Also known as:** GHSA-mvqj-h65j-wcmq

## What is MAL-2026-13821?

MAL-2026-13821 is a malicious package in mnchfnvbue1, published on 12 Aug 2026. 

### Official description

The tarball contains a single file, index.html, declared as the package main. The HTML contains heavily obfuscated JavaScript that mimics a Cloudflare 'Just a moment...' interstitial and, after a 1-second timeout, decodes a string-array to build a URL and calls window.location.replace to navigate a browser to that URL. There are no npm lifecycle scripts (preinstall/install/postinstall/prepare), no bin entry, and main points at a non-JavaScript file, so npm install and require() do not execute this code on an installer's machine. The redirect only fires in a browser rendering the HTML. The package appears to be registry abuse (using npm to host an obfuscated browser redirect asset) rather than a supply-chain attack against installers.

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-2026-13821?

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-2026-13821 is a malicious package: mnchfnvbue1 (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-2026-13821/ (Markdown: https://insights.sbomify.com/MAL-2026-13821/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-13821

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-13821/
Summaries are generated and may contain mistakes; the official description above is the record.