fabric-asset-pipelinenpm
Advisory published Updated
fabric-asset-pipeline is a confirmed malicious npm package (MAL-2026-17224) that steals credentials and exfiltrates sensitive data (malicious versions 1.0.0, 1.0.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in fabric-asset-pipeline (npm)
What this malware does
[email protected] declares a postinstall hook that runs index.js on npm install. index.js is heavily obfuscated (obfuscator.io-style rotated string array plus base64+RC4 decoding of identifiers and URLs, with newline/regex anti-formatting hooks) and implements a Minecraft credential stealer: functions stealLauncherAccounts(), stealAltLaunchers(), and readSessionDump() read account credential stores from the official Minecraft launcher (launcher_accounts.json / launcher_profiles.json) as well as Prism/MultiMC, TLauncher, Modrinth, PolyMC, and GDLauncher, plus a session dump from the OS temp directory. Extracted account names, access tokens, and refresh tokens are POSTed via https.request to a hardcoded webhook whose URL is RC4-decoded at runtime. A companion sendInfo() call ships os.hostname(), os.userInfo().username, os.platform()/os.release(), and the recovered Minecraft username to the same endpoint. None of this behavior is part of the package's advertised 'asset loader bridge' purpose, and the obfuscation deliberately conceals both the exfiltration functions and the destination URL.
The OpenSSF Package Analysis project identified 'fabric-asset-pipeline' @ 1.0.0 (npm) as malicious.
It is considered malicious because:
- The package communicates with a domain associated with malicious activity.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for fabric-asset-pipeline (2 malicious versions).
If you installed it — respond
fabric-asset-pipeline is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If fabric-asset-pipeline was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
- OpenSSF: Package Analysis · finder
Detect & block this
O3 blocks fabric-asset-pipeline-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.