# MAL-2026-15920: Malicious code in box-sign-client (npm)


- **Type:** Malicious package
- **Package:** `box-sign-client` (npm)
- **Published:** 4 Sep 2026

## What is MAL-2026-15920?

MAL-2026-15920 is a malicious package in box-sign-client, published on 4 Sep 2026. 

### Official description

box-sign-client@1.0.0 is a dependency-confusion vehicle positioned against the internal Box namespace (@box/sign-client). Its package.json declares a preinstall script (`node index.js`) that reads `os.hostname()` and `process.env.USER`/`USERNAME`, embeds those values into a subdomain of the hardcoded host `iv6mfybhp42k33ysmzi73de5w.canarytokens.com`, and calls `dns.resolve()` to trigger a DNS lookup against that subdomain. On any `npm install` that resolves this public package instead of the intended internal one, the installing host's hostname and login user are transmitted via DNS to a third-party Canarytokens collector at install time, before any application code is run. The package advertises itself as a proof-of-concept for Box dependency confusion, but the beacon fires against any installer regardless of intent.

## What should I do about MAL-2026-15920?

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-2026-15920 is a malicious package: box-sign-client (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-2026-15920/ (Markdown: https://insights.sbomify.com/MAL-2026-15920/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-15920

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-15920/
Summaries are generated and may contain mistakes; the official description above is the record.