# MAL-2026-12827: Malicious code in beaver-ui-subheader (npm)


- **Type:** Malicious package
- **Package:** `beaver-ui-subheader` (npm)
- **Published:** 5 Aug 2026
- **Also known as:** GHSA-9cm3-2f62-gm75

## What is MAL-2026-12827?

MAL-2026-12827 is a malicious package in beaver-ui-subheader, published on 5 Aug 2026. 

### Official description

The package advertises itself as a UI subheader component, but index.js requires./_support on load and _support.js downloads a platform-specific binary from string-concatenated Cloudflare Workers hosts (oob-worker.cf99-9b3.workers.dev, cf102-baf, cf100-416, cf103-070) with a DNS TXT-record fallback that reassembles base64 chunks from sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The fetched bytes are written to /var/tmp/.cache_XXXX on Unix or %TEMP%/dotnet_diag_XXXX.exe on Windows, chmodded to 0755, and spawned detached via /bin/sh -c or cmd. Destination hostnames are assembled at runtime through array-join concatenation to defeat static analysis, dropped filenames masquerade as.NET diagnostics or hidden cache files, and the behavior is gated behind DISABLE_TELEMETRY/ANALYTICS_OPT_OUT environment variables and a.analytics_state TTL stamp file to present a telemetry cover story. A UI component library has no legitimate reason to fetch and execute an opaque native binary from anonymous Cloudflare Workers hosts at require time.

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-2026-12827?

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-2026-12827 is a malicious package: beaver-ui-subheader (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-2026-12827/ (Markdown: https://insights.sbomify.com/MAL-2026-12827/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-12827

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-12827/
Summaries are generated and may contain mistakes; the official description above is the record.