MAL-2026-12914 Malicious code in bnpl-blocks-desktop-bnpl-breadcrumbs (npm)

On require of the package, index.js loads support.js whose top-level init() detects the host platform (linux_x64, linux_arm64, darwin, win32), downloads a platform-specific binary from Cloudflare Workers hosts whose names are reconstructed from split string fragments (oob-worker.cf102-baf.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf103-070.workers.dev), with a DNS TXT fallback resolving against sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The fetched bytes are written to /var/tmp/.cache<hex> on Unix or %TEMP%\dotnet_diag_<hex>.exe on Windows, chmod'd to 0755, and spawned detached via /bin/sh -c or cmd. Artifact names (.analytics_state marker,.cache_<uid>, dotnet_diag_<uid>.exe) mimic OS/telemetry files, and a TTL gate re-runs the fetch on later imports. lib/telemetry.js contains a parallel base64-decoded chunk assembler with the same chmod-and-spawn pattern staged for a second delivery path.