# MAL-2026-17626: Malicious code in serpacksven1 (npm)


- **Type:** Malicious package
- **Package:** `serpacksven1` (npm)
- **Published:** 5 Oct 2026
- **Also known as:** GHSA-696v-rr55-26pc

## What is MAL-2026-17626?

MAL-2026-17626 is a malicious package in serpacksven1, published on 5 Oct 2026. 

### Official description

The tarball ships no JavaScript — the declared `main: index.js` is absent — and contains only 10 byte-identical copies of a PowerShell dropper under misleading extensions (`1.png`, `client.doc`, `client.doc.1`, `json.txt`, extensionless `client`, all sha256 e9dff494...). The script hides the console window via Win32 APIs, concatenates ~150 base64 chunks, XOR-decodes them with single-byte key 89, reflectively resolves `[System.Reflection.Assembly].Load` through char-code-obfuscated type strings, and invokes the decoded in-memory.NET assembly. The package has no lifecycle scripts and no importable surface, so `npm install` alone does not execute the payload; the harm fires when a second-stage tool or downstream workflow sources any of the disguised files (e.g. `powershell -File client.doc`), delivering full-host code execution of an attacker-controlled.NET assembly on Windows. The multi-extension disguise, byte-identical duplication, and absence of any legitimate package content show this is a payload-staging artifact published to npm rather than a software package.

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-2026-17626?

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-2026-17626 is a malicious package: serpacksven1 (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-2026-17626/ (Markdown: https://insights.sbomify.com/MAL-2026-17626/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-17626

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-17626/
Summaries are generated and may contain mistakes; the official description above is the record.