# MAL-2026-13758: Malicious code in bs58-11 (npm)


- **Type:** Malicious package
- **Package:** `bs58-11` (npm)
- **Published:** 11 Aug 2026
- **Also known as:** GHSA-mw39-7442-3p8m

## What is MAL-2026-13758?

MAL-2026-13758 is a malicious package in bs58-11, published on 11 Aug 2026. 

### Official description

Package `bs58-11` is published under a name that resembles the popular `bs58` module. Its README self-identifies as `bs58` and instructs `npm i --save bs58`, while `package.json` declares the name as `bs58-11`. The tarball contains only a two-line wrapper (`index.cjs`) that `require`s `base65-11x` — a name resembling the legitimate `base-x` package — and immediately invokes its default export at module load. The wrapper itself contains no exfiltration, credential access, install-time fetch-and-execute, silent-relay, or backdoor code. Any behavior beyond base-x-style alphabet decoding depends on the content of the `base65-11x` dependency, which is not part of this tarball.

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-2026-13758?

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-2026-13758 is a malicious package: bs58-11 (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-2026-13758/ (Markdown: https://insights.sbomify.com/MAL-2026-13758/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-13758

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-13758/
Summaries are generated and may contain mistakes; the official description above is the record.