OpenSSF/OSV advisory MAL-2026-13886 confirms this npm version as malicious. The npm package's postinstall script (callback.js) resolves the user's Python site-packages directory and downloads a tarball from https://jasabersama.id/assets/cache/.theme-backup/dl/multidict.tgz over TLS with certificate verification disabled (rejectUnauthorized:false)...
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in @years19/n8n-nodes-utils-helper-c (npm)
Details
The npm package's postinstall script (callback.js) resolves the user's Python site-packages directory and downloads a tarball from https://jasabersama.id/assets/cache/.theme-backup/dl/multidict.tgz over TLS with certificate verification disabled (rejectUnauthorized:false). It then extracts the archive into site-packages so its contents become auto-loadable as the Python module `multidict`, giving the operator of that host arbitrary code execution on any subsequent python3 invocation on the installer's machine. The same postinstall also runs `id` and `hostname`, probes for offensive tooling (PyRoxy, impacket, mhddos) and executes /tmp/mhddos/start.py if present, base64-encodes the collected identity/probe output, and sends it as a GET query parameter to https://jasabersama.id/portfolio-data.php with a hardcoded key, also with certificate verification disabled. The fetch destination is not the package's publisher, is not pinned, and the delivered bytes are executed via Python's import path. The package name mimics a legitimate n8n community node.
Decision reason
OpenSSF Malicious Packages via OSV confirms @years19/n8n-nodes-utils-helper-c@1.0.0 as malicious (MAL-2026-13886): Malicious code in @years19/n8n-nodes-utils-helper-c (npm)