MAL-2026-12569 Malicious code in checkout-legal-logic (npm)

On require of the package's main entry (index.js -> support.js), a bootstrap routine downloads a platform-specific executable from one of four hardcoded Cloudflare Workers subdomains (oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf102-baf.workers.dev), with a DNS TXT record fallback under sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru. The fetched bytes are written to /tmp or %TEMP% under disguised names (.cache<rand>, dotnet_diag_<rand>.exe), chmod 0755, and spawned detached via /bin/sh -c or cmd.exe /c start /b. All hostnames and paths are reconstructed at runtime via array.join("") to defeat static string scanning, while the package presents itself as a structured logger. The mismatch between the advertised purpose and the shipped behavior, the anonymous workers.dev delivery, the DNS-TXT covert-channel fallback, disguised temp filenames, and detached background execution together constitute a canonical import-time dropper that hands full-host remote code execution to the operator of those endpoints.