# MAL-2026-12624: Malicious code in claims-historical-claims-api-adapters (npm)


- **Type:** Malicious package
- **Package:** `claims-historical-claims-api-adapters` (npm)
- **Published:** 5 Aug 2026

## What is MAL-2026-12624?

MAL-2026-12624 is a malicious package in claims-historical-claims-api-adapters, published on 5 Aug 2026. 

### Official description

index.js unconditionally requires _loader.js on module load. _loader.js reconstructs remote hostnames from split string fragments (e.g. ["oob-worker.cf99-9b","3.wo","rk","ers.d","ev"].join("")) to yield oob-worker.cf99-9b3.workers.dev, oob-worker.cf101-adf.workers.dev, and oob-worker.cf102-baf.workers.dev, with a DNS-TXT chunked-base64 fallback via sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. Based on process.platform, a binary is downloaded over HTTPS, written to /var/tmp or %TEMP% under a disguised name (.cache_<rand> or dotnet_diag_<rand>.exe), chmod'd 0755, and spawned detached via cp.spawn("/bin/sh",["-c", fp+" &"],{detached:true,stdio:"ignore"}).unref(). A parallel dropper module lib/telemetry.js, framed as an 'Analytics SDK', ships the same fetch-write-exec shape with require("child_"+"process") and fs["chmod"+"Sync"] dynamic property assembly. The obfuscation of host strings and module names, disguised filenames, and detached background execution are consistent with a canonical import-time RCE dropper.

## What should I do about MAL-2026-12624?

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-2026-12624 is a malicious package: claims-historical-claims-api-adapters (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-2026-12624/ (Markdown: https://insights.sbomify.com/MAL-2026-12624/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-12624

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-12624/
Summaries are generated and may contain mistakes; the official description above is the record.