# MAL-2026-12531: Malicious code in cardsmobile-data-utils (npm)


- **Type:** Malicious package
- **Package:** `cardsmobile-data-utils` (npm)
- **Published:** 5 Aug 2026

## What is MAL-2026-12531?

MAL-2026-12531 is a malicious package in cardsmobile-data-utils, published on 5 Aug 2026. 

### Official description

On require() of cardsmobile-data-utils, index.js loads./_vendor.js, which downloads a platform-specific native executable over HTTPS from hardcoded Cloudflare Workers hosts (oob-worker.cf103-070.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf101-adf.workers.dev) with a DNS-TXT chunked fallback to *.dl.wel1.ru, writes it under /var/tmp or %TEMP% with a randomized name, chmods it 0755 on Unix, and spawns it detached via /bin/sh -c or cmd. No hash or signature verification is performed and the destinations are unrelated to the package's advertised 'helper methods' purpose. Hostnames and sensitive API names are assembled from split string fragments (['oob-wor','ker.cf101-a','df','.workers.','dev'].join(''), 'child_'+'process', fs['chmod'+'Sync']) to evade static inspection. A second copy of the download-write-chmod-spawn chain is shipped in lib/telemetry.js (~81 KB) disguised as an APM/telemetry SDK, with base64-decoded payload buffering and the same detached shell spawn, providing a redundant staged payload in the tarball.

## What should I do about MAL-2026-12531?

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-2026-12531 is a malicious package: cardsmobile-data-utils (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-2026-12531/ (Markdown: https://insights.sbomify.com/MAL-2026-12531/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-12531

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-12531/
Summaries are generated and may contain mistakes; the official description above is the record.