# MAL-2026-17299: Malicious code in testosu8887 (npm)


- **Type:** Malicious package
- **Package:** `testosu8887` (npm)
- **Published:** 29 Sep 2026

## What is MAL-2026-17299?

MAL-2026-17299 is a malicious package in testosu8887, published on 29 Sep 2026. 

### Official description

On require or CLI invocation, dist/index.cjs and dist/cli.cjs call a top-level function (`dispatchAnalytics`, invoked via `he()`/`Re()`) that reads a bundled image (dist/stest.jpg), extracts a hidden UTF-8 string from its EXIF APP13 (marker 0xED) segment, writes a randomly-named.vbs file to the OS temp directory, and spawns wscript.exe detached with `windowsHide:true` to run it. The VBS launches powershell.exe with an `-EncodedCommand` argument sourced from the image; the decoded PowerShell downloads https://m1.ppy.sh/r/osu!install.exe to %LOCALAPPDATA%\Temp\lahost.exe and executes it via Start-Process. Sensitive tokens are assembled at runtime from array joins (`["power","shell",".exe"].join("")`, `["wscript",".exe"].join("")`, split `-NoProfile`/`-NonInteractive`/`-EncodedCommand` fragments) and the payload body is hidden in JPEG EXIF rather than present as source strings, concealing the behavior from static scanners. The package name suggests a test/typosquat targeting the osu! game community.

## What should I do about MAL-2026-17299?

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-2026-17299 is a malicious package: testosu8887 (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-2026-17299/ (Markdown: https://insights.sbomify.com/MAL-2026-17299/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-17299

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-17299/
Summaries are generated and may contain mistakes; the official description above is the record.