MAL-2026-5689 Malicious code in ecto-rust-read-f3a9c1 (npm)

On install, postinstall.js evaluates a targeting heuristic (isRealTarget) that fires only when the build environment looks like a real corporate CI/Docker host — cwd not under /tmp, hostname not matching researcher patterns ('hetzner','nijin','ec2.internal'), and either the npm registry points at a private mirror (nexus.local/verdaccio) or the hostname is a 12-hex container ID with /app/ cwd. When the heuristic matches, the script writes /usr/local/bin/.spectral-shell (mode 0755) containing a /bin/sh reverse shell to snnkj-159-153-180-200.run.pinggy-free.link:38493 via /dev/tcp, then installs a root cron entry at /etc/cron.d/spectral-shell ('* * * * * root /usr/local/bin/.spectral-shell') with a fallback to the user crontab, starts cron, and immediately spawns the shell detached. It also PUTs JSON containing uid, hostname, and cwd to http://154.57.164.71:31289/api/modules/ECT-472839 to confirm compromise to the operator. The combination — interactive reverse shell, root cron persistence every minute, sandbox-evasion targeting of enterprise build hosts, and a hardcoded bare-IP HTTP beacon — is a textbook supply-chain backdoor delivered via npm lifecycle.

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.