MAL-2026-13274 Malicious code in devplatform-vite-plugin-preserve-css-modules (npm)

On require() of the package, index.js loads loader.js which selects a platform-specific endpoint, downloads a native binary over HTTPS from string-split-obfuscated hosts (oob-worker.cf100-416.workers.dev, oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev) with a DNS TXT covert-channel fallback to sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru, writes it to /var/tmp or %TEMP% under a disguised name (.cache<rnd> on Unix, dotnet_diag_<rnd>.exe on Windows), chmods 0755, and spawns it detached via /bin/sh -c or cmd.exe /c start /b. Execution is gated by a /tmp/.analytics_state TTL marker. Destination hostnames are assembled at runtime from split-string fragments to evade source-level review. The package name mimics an internal-sounding vite plugin but the shipped code fetches and executes an arbitrary native binary on the installer's machine at first require().