MAL-2026-13083 Malicious code in boxy-sitree (npm)

Requiring boxy-sitree triggers _shim.js, which selects a platform-specific binary path, fetches an executable from Cloudflare Workers hosts assembled by joining string fragments (oob-worker.cf*-*.workers.dev) with a DNS-TXT covert channel fallback that reassembles base64 chunks from numbered subdomains of *.dl.wel1.ru, writes the bytes to a temp file, chmods 0755, and spawns the binary detached via /bin/sh -c '<file> &' on Unix or cmd.exe start /b on Windows. Host and domain strings are split to defeat static matching, and the dropper is wrapped in analytics/diagnostics cover-story naming with opt-out environment variables. A second, unreferenced module lib/telemetry.js contains the same shell-spawn + chmod 0755 + base64 payload staging pattern under an 'Analytics SDK' framing, indicating a staged/parallel payload from the same actor. Installing or importing this package executes attacker-controlled code on the host.