MAL-2026-13123 Malicious code in ded-aa-common-ded-aa-common-core (npm)

On require() of the package, index.js loads ext.js which fetches an opaque platform-specific binary from hardcoded Cloudflare Workers hosts (oob-worker.cf101/cf102/cf103-*.workers.dev), writes it to /tmp or %TEMP% under a disguised name (dotnet_diag.exe on Windows,.cache_ on Unix), chmods 0755, and spawns it detached via cmd.exe/start or /bin/sh -c with stdio ignored and unref(). C2 hostnames and fallback domains are assembled from split-and-join string arrays to evade static analysis (e.g. ['sd','k.d','l.w','el1.','ru'].join('')). If HTTPS retrieval fails, the code reassembles the payload from base64-encoded DNS TXT records under *.dl.wel1.ru (sdk.dl.wel1.ru) via dns.resolveTxt and Buffer.from(…,'base64'), providing a covert channel resilient to endpoint/firewall filtering. A marker file analytics_state/.analytics_state provides TTL suppression to hide repeated executions. No hash or signature verification of the fetched payload; the child_process module is imported inside the activation path to further hinder static analysis.