MAL-2026-12200 Malicious code in simple-date-formatter-util-11 (npm)

Package advertises itself as a trivial date-formatting utility (index.js exports a one-line formatDate wrapper) but ships a package.json postinstall hook that runs on npm install and executes a shell one-liner harvesting installer identity (id, hostname, uname), container and Kubernetes indicators (/proc/1/cgroup, docker.sock, /var/run/secrets/kubernetes.io/serviceaccount/token), capabilities, mounts, network configuration, and environment variables filtered by kube|aws|token|secret|key|pass|role|region|cluster|node|service|container. The aggregated output is POSTed to http://safjhdvsfwzhieemkdzbgr54r0yjhrmok.oast.fun/escinfo, an interact.sh/OAST-style callback host. The tarball additionally ships postinstall.js, which reads ~/.ssh directory contents and POSTs a JSON payload (SSH key filenames, username, platform) to a hardcoded IP 124.221.154.135:443/post. The advertised purpose does not match the install-time behavior.