# MAL-2026-6340: Malicious code in rainbownkit (npm)


- **Type:** Malicious package
- **Package:** `rainbownkit` (npm)
- **Published:** 23 Jun 2026
- **Also known as:** GHSA-vj5m-3jrw-83gx

## What is MAL-2026-6340?

MAL-2026-6340 is a malicious package in rainbownkit, published on 23 Jun 2026. 

### Official description

Package 'rainbownkit' is a single-character typosquat of the popular Web3 library 'rainbowkit'. The shipped source, README, repository URL, and author metadata are copied verbatim from the unrelated 'big.js' arbitrary-precision math library — a developer installing this expecting RainbowKit instead receives big.js with an injected covert loader. The package's main entry (big.js and big.mjs, both referenced via `main` and `exports`) contains an injected try/catch around line 606 that runs at require/import time: `const doc = require("parket-slot"); doc.from_str().then(e => {}).catch(e => {})`. The 'parket-slot' module is not declared in package.json and would be pulled in transitively via the package's only declared runtime dependency 'log-taker' (`^0.0.9`), an undocumented niche package with no relation to the package's claimed purpose. All errors are silently swallowed, making the hidden execution invisible to the consumer. Anyone who runs `require('rainbownkit')` (or any code that imports it) executes whatever code the 'parket-slot' / 'log-taker' chain delivers at that moment — a classic two-hop dependency-confusion supply-chain payload combined with name impersonation of a high-traffic Web3 package.

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-2026-6340?

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-2026-6340 is a malicious package: rainbownkit (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-2026-6340/ (Markdown: https://insights.sbomify.com/MAL-2026-6340/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-6340

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-6340/
Summaries are generated and may contain mistakes; the official description above is the record.