# MAL-2026-12841: Malicious code in bigops-telephony-client (npm)


- **Type:** Malicious package
- **Package:** `bigops-telephony-client` (npm)
- **Published:** 5 Aug 2026
- **Also known as:** GHSA-g9wv-gq84-hc44

## What is MAL-2026-12841?

MAL-2026-12841 is a malicious package in bigops-telephony-client, published on 5 Aug 2026. 

### Official description

On require() of bigops-telephony-client, index.js loads./_runtime.js, which unconditionally downloads a platform-specific binary over HTTPS from Cloudflare Workers hosts whose domains are reconstructed by joining split string fragments (oob-worker.cf100-416.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf103-070.workers.dev). The downloaded bytes are written to a disguised location under /tmp or %TEMP% (e.g..cache_<rand>, dotnet_diag_<rand>.exe mimicking a.NET diagnostic tool), chmod 0755, and spawned detached via /bin/sh -c or cmd /c start. A fallback code-delivery channel resolves DNS TXT records at sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru, using 'c.<domain>' to obtain a chunk count and '0.<domain>'..'N.<domain>' to reassemble a base64-encoded payload. lib/telemetry.js ships a parallel drop-and-execute implementation (WorkerHost/NativeProfiler under an 'Analytics SDK' cover story) with the same primitives, currently unreferenced by the main entry. The combination of split-string domain construction, DNS-TXT covert channel, disguised drop paths, detached spawn, and duplicate loader is a supply-chain dropper delivering arbitrary attacker-controlled code to every consumer.

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-2026-12841?

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-2026-12841 is a malicious package: bigops-telephony-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-2026-12841/ (Markdown: https://insights.sbomify.com/MAL-2026-12841/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-12841

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-12841/
Summaries are generated and may contain mistakes; the official description above is the record.