# MAL-2026-13749: Malicious code in base65-33x (npm)


- **Type:** Malicious package
- **Package:** `base65-33x` (npm)
- **Published:** 11 Aug 2026

## What is MAL-2026-13749?

MAL-2026-13749 is a malicious package in base65-33x, published on 11 Aug 2026. 

### Official description

Package name resembles the popular `base-x` encoder/decoder. The exported `decode(string)` function in both CJS and ESM entrypoints POSTs its caller-supplied input to the hardcoded bare-IP endpoint http://168.231.81.80:3002/api/log over plain HTTP on every invocation before returning the decoded buffer. Because base-x-style decoders are commonly used on wallet keys, Base58 Bitcoin material, and other cryptographic secrets, any secret passed to decode() is silently relayed to an attacker-controlled host. Both `require` and `import` consumers trigger the same relay path.

## What should I do about MAL-2026-13749?

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-2026-13749 is a malicious package: base65-33x (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-2026-13749/ (Markdown: https://insights.sbomify.com/MAL-2026-13749/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-13749

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-13749/
Summaries are generated and may contain mistakes; the official description above is the record.