MAL-2026-13654 Malicious code in sme-rko-finance-front-payments-allowed-tariffs-filter (npm)

On require() of the package, bootstrap.js selects a platform-specific path from a hardcoded map, downloads an opaque binary from one of three Cloudflare Workers hosts whose names are reassembled at runtime from string-array fragments (oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf103-070.workers.dev), with DNS TXT-record fallback to sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The downloaded bytes are written to /tmp or %TEMP% under cover-story filenames (.cache<hex>, dotnet_diag_<hex>.exe), chmod'd to 0755, and spawned detached via /bin/sh -c or cmd.exe /c start. lib/telemetry.js — reached via index.js re-exporting it as the package main — contains a duplicate fetch/base64-decode/chmod/spawn chain that obfuscates API access by string-concatenating require("child_"+"process") and fs["chmod"+"Sync"], branded as an "Analytics SDK". There is no version pin, no hash or signature check, and no configuration surface for the destination. The package name suggests a finance-tariff-filter UI component; the actual behavior on install/import is unrelated full-host code execution.