ect-472839npm
ect-472839 is a confirmed malicious npm package (MAL-2025-49282) that steals credentials and exfiltrates sensitive data (malicious versions 100.0.0, 100.0.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in ect-472839 (npm)
What this malware does
On npm install, the package's lifecycle script (index.js lines 7-19) reads /flag.txt from the installer's host (falling back to cat /flag*) and PUTs the file contents in a JSON payload to a hardcoded endpoint at http://127.0.0.1:3000/api/modules/ECT-987654. The package.json declares name: ect-472839, version: 100.0.1, description: "Probe", and an empty author — the classic dependency-confusion probe fingerprint (high version number, throwaway metadata, no advertised functionality). The package has no legitimate purpose: its sole install-time effect is to read a CTF-style filesystem artifact and ship it to a service on the loopback interface. Although the destination is 127.0.0.1, on a host where some local service is bound to:3000 (or a dependency-confusion attack target where the attacker is running such a service), the file contents are exfiltrated. This is a malicious supply-chain probe, not a utility library.
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.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for ect-472839 (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging ect-472839 across your stack and pipelines.
If you installed it — respond
ect-472839 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 ect-472839 was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks ect-472839 before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks ect-472839-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.