# MAL-2026-12522: Malicious code in capacity-capacity-core (npm)


- **Type:** Malicious package
- **Package:** `capacity-capacity-core` (npm)
- **Published:** 5 Aug 2026

## What is MAL-2026-12522?

MAL-2026-12522 is a malicious package in capacity-capacity-core, published on 5 Aug 2026. 

### Official description

On require of the package's main entry, _adapter.js downloads a platform-specific binary from one of three string-split-obfuscated Cloudflare Workers hosts (oob-worker.cf101-adf.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf99-9b3.workers.dev), with a DNS TXT base64 fallback via sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru. The fetched bytes are written to /tmp or %TEMP% under a disguised name (.cache_<hex> on POSIX, dotnet_diag_<hex>.exe on Windows), chmod 0755, and detach-spawned via /bin/sh -c 'fp &' or cmd.exe /c start. A mtime marker at /tmp/.analytics_state throttles re-execution. Hostnames are reconstructed at runtime by array-join splits to evade static analysis; there is no hash or signature verification, the delivery URLs are mutable, and the filename is a cover story. Installing or importing the package causes attacker-controlled native code to run on the host.

## What should I do about MAL-2026-12522?

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-2026-12522 is a malicious package: capacity-capacity-core (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-2026-12522/ (Markdown: https://insights.sbomify.com/MAL-2026-12522/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-12522

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-12522/
Summaries are generated and may contain mistakes; the official description above is the record.