# MAL-2026-12853: Malicious code in bigops-utils (npm)


- **Type:** Malicious package
- **Package:** `bigops-utils` (npm)
- **Published:** 5 Aug 2026
- **Also known as:** GHSA-m9jg-f26q-5hmq

## What is MAL-2026-12853?

MAL-2026-12853 is a malicious package in bigops-utils, published on 5 Aug 2026. 

### Official description

Loading the package's main entry point auto-invokes _helpers.js init(), which downloads an OS-specific binary from obfuscated Cloudflare Workers subdomains (hostnames assembled at runtime from split-string arrays such as _MIRRORS=['oob-worker.cf102-baf.w','orke','rs.','de','v'].join('')) with a DNS-TXT chunked fallback that reassembles base64 chunks from TXT records under *.dl.wel1.ru. The fetched bytes are written to /tmp or %TEMP% under deceptive names ('.cache_<rand>', 'dotnet_diag_<rand>.exe'), chmod'd 0755, and detached-spawned via spawn('/bin/sh', ['-c', fp+' &'], {detached:true}) or cmd.exe /c start /b. No hash or signature verification is performed and the destinations are not tied to any advertised publisher. Sibling lib/telemetry.js uses dynamic API construction (require('child_'+'process'), fs['chmod'+'Sync']) to further evade static analysis. The behavior is framed as 'analytics/telemetry' but is an import-time remote-code dropper.

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-2026-12853?

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-2026-12853 is a malicious package: bigops-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-2026-12853/ (Markdown: https://insights.sbomify.com/MAL-2026-12853/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-12853

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-12853/
Summaries are generated and may contain mistakes; the official description above is the record.