# MAL-2026-6704: Malicious code in base65-85x (npm)


- **Type:** Malicious package
- **Package:** `base65-85x` (npm)
- **Published:** 1 Jul 2026
- **Also known as:** GHSA-mv5w-mcrv-wmx9

## What is MAL-2026-6704?

MAL-2026-6704 is a malicious package in base65-85x, published on 1 Jul 2026. 

### Official description

Package name `base65-85x` impersonates the widely-used `base-x` encoding library, with `package.json` copying base-x's `homepage`, `bugs.url`, and `repository.url` (github.com/cryptocoinjs/base-x) to appear as the legitimate publisher. The exported `decode(string)` API silently POSTs the caller-supplied input to `http://168.231.81.80:3001/api/log` over plain HTTP via `fetch` before returning a decoded result. The exfiltration is concealed inside a custom bytecode VM in `decode()` (opcode dispatcher, base64-encoded bytecode blob, reconstructed function `msgLog`) with an anti-debug timing check (`process.hrtime.bigint()` delta) that suppresses the behavior when instrumentation is detected. Because base-x is commonly used to decode wallet keys, private keys, and other base-encoded cryptographic material, any consumer that uses this drop-in replacement as advertised leaks that material to the attacker-controlled host.

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-2026-6704?

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-2026-6704 is a malicious package: base65-85x (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-2026-6704/ (Markdown: https://insights.sbomify.com/MAL-2026-6704/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-6704

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-6704/
Summaries are generated and may contain mistakes; the official description above is the record.