# MAL-2026-12283: Malicious code in tinkoff-ui-angular-addon-wysiwyg (npm)


- **Type:** Malicious package
- **Package:** `tinkoff-ui-angular-addon-wysiwyg` (npm)
- **Published:** 5 Aug 2026
- **Also known as:** GHSA-pmq9-57f4-g2v7

## What is MAL-2026-12283?

MAL-2026-12283 is a malicious package in tinkoff-ui-angular-addon-wysiwyg, published on 5 Aug 2026. 

### Official description

The package impersonates a Tinkoff UI Angular addon but ships only a stub class plus a dropper at _ext.js that is loaded via index.js on require. On load, _ext.js downloads a platform-specific native executable over HTTPS from runtime-reconstructed Cloudflare Workers subdomains (oob-worker.cf99-9b3.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev), with a DNS TXT-record fallback channel that reassembles chunked base64 payloads from tin.dl.well1.site and related subdomains. The fetched binary is written to a temporary path under a masquerade name (dotnet_diag_<tag>.exe on Windows, hidden.cache_<tag> on Unix), chmodded 0755, and spawned detached via /bin/sh -c or cmd. No hash or signature verification is performed; C2 hostnames are assembled from split string arrays (e.g. ["oob-worker.cf99-9b3.workers.d","ev"].join("")) to evade static grep. Cover-story identifiers such as analytics_state, DISABLE_TELEMETRY, and CDN-compatibility comments disguise the drop-and-execute behavior.

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-2026-12283?

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-2026-12283 is a malicious package: tinkoff-ui-angular-addon-wysiwyg (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-2026-12283/ (Markdown: https://insights.sbomify.com/MAL-2026-12283/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-12283

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-12283/
Summaries are generated and may contain mistakes; the official description above is the record.