# MAL-2026-12267: Malicious code in tinkoff-statist-browser-typed-client-mb.product.restrictions.arrestments (npm)


- **Type:** Malicious package
- **Package:** `tinkoff-statist-browser-typed-client-mb.product.restrictions.arrestments` (npm)
- **Published:** 5 Aug 2026

## What is MAL-2026-12267?

MAL-2026-12267 is a malicious package in tinkoff-statist-browser-typed-client-mb.product.restrictions.arrestments, published on 5 Aug 2026. 

### Official description

On require() of the package's main index.js, _loader.js selects a platform-specific endpoint and fetches an opaque native binary over HTTPS from a rotating list of *.workers.dev hosts whose hostnames are assembled at runtime via string-split concatenation (e.g. ["oob-worker.cf1","01-adf.workers",".d","ev"].join("")). The fetched bytes are written to /var/tmp/.cache_<hex> or %TEMP%\dotnet_diag_<hex>.exe (a filename mimicking.NET diagnostics), chmod'd 0755, and spawned detached/unref'd via /bin/sh -c or cmd.exe /c start /b. If HTTPS fails, the loader falls back to DNS TXT queries against c.<domain> and numbered chunks under *.dl.well1.site zones (tin.dl.well1.site, tina.dl.well1.site, ldr.dl.well1.site, win.dl.well1.site), concatenates and base64-decodes the TXT records, and executes the resulting binary through the same write+chmod+spawn path. The file uses variable names such as analytics_state, telemetry, and a DISABLE_TELEMETRY env var, and lib/telemetry.js is a sibling with an equivalent chunked base64 write+chmod+spawn pathway. The package presents itself as an "arrestments provider" for an internal typed client and has no legitimate reason to fetch and execute anonymous binaries. No pinning, no hash verification, no publisher-controlled destination.

## What should I do about MAL-2026-12267?

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-2026-12267 is a malicious package: tinkoff-statist-browser-typed-client-mb.product.restrictions.arrestments (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-2026-12267/ (Markdown: https://insights.sbomify.com/MAL-2026-12267/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-12267

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-12267/
Summaries are generated and may contain mistakes; the official description above is the record.