# MAL-2026-12757: Malicious code in devplatform-spa-di (npm)


- **Type:** Malicious package
- **Package:** `devplatform-spa-di` (npm)
- **Published:** 5 Aug 2026

## What is MAL-2026-12757?

MAL-2026-12757 is a malicious package in devplatform-spa-di, published on 5 Aug 2026. 

### Official description

On require('devplatform-spa-di'), index.js loads _polyfill.js which fetches a platform-specific native binary from hardcoded Cloudflare Workers subdomains (oob-worker.cf100-416.workers.dev, cf99-9b3.workers.dev, cf101-adf.workers.dev, cf102-baf.workers.dev), with a DNS-TXT base64 fallback resolving through sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru. The fetched bytes are written to /tmp/.cache_<rand> on POSIX or %TEMP%\dotnet_diag_<rand>.exe on Windows, chmod 0755, and spawned detached via /bin/sh -c or cmd.exe /c start /b. Host strings and DNS domains are reconstructed at runtime by joining split array fragments (e.g. ["oob-worker.cf100-416.worke","rs.dev"].join("")) and cover-story comments frame the dropper as telemetry, with DISABLE_TELEMETRY/ANALYTICS_OPT_OUT/DO_NOT_TRACK env-var gates and an EXPIRE_SEC mtime stamp implementing dormancy and once-per-host gating. No hash or signature verification is performed. The package's advertised purpose is a small SPA dependency-injection helper, unrelated to native binary execution.

## What should I do about MAL-2026-12757?

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-2026-12757 is a malicious package: devplatform-spa-di (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-2026-12757/ (Markdown: https://insights.sbomify.com/MAL-2026-12757/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-12757

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-12757/
Summaries are generated and may contain mistakes; the official description above is the record.