# MAL-2026-4267: Malicious code in @newline53/newline-ts-sdk (npm)


- **Type:** Malicious package
- **Package:** `@newline53/newline-ts-sdk` (npm)
- **Published:** 23 May 2026

## What is MAL-2026-4267?

MAL-2026-4267 is a malicious package in @newline53/newline-ts-sdk, published on 23 May 2026. 

### Official description

On `npm install`, the postinstall hook (`node install.js`) collects `os.hostname()` and `os.userInfo().username` along with the package name, encodes them as a DNS subdomain of `mjcfux88wjjahplabxdauc6bl.canarytokens.com`, and beacons out via DNS resolution (`dns.lookup`/`dns.resolve`) and HTTP requests (shelled `curl`/`wget` to `http://<host-username-pkg>.mjcfux88wjjahplabxdauc6bl.canarytokens.com`). The package has no real functionality — `index.js` is `module.exports = {}` — and `package.json` carries placeholder author metadata (a 32-char hex string with no homepage or repository). The structure (empty main, recon-only postinstall, canarytoken endpoint) is the canonical dependency-confusion probe: an attacker publishes a public npm package matching an internal scope name to detect whether private builds inside a target organization resolve to and install the public name. The exfiltrated hostname/username identifies the victim environment to the attacker.

The OpenSSF Package Analysis project identified '@newline53/newline-ts-sdk' @ 1.0.1 (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-2026-4267?

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-2026-4267 is a malicious package: @newline53/newline-ts-sdk (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-2026-4267/ (Markdown: https://insights.sbomify.com/MAL-2026-4267/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-4267

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-4267/
Summaries are generated and may contain mistakes; the official description above is the record.