MAL-2026-13016 Malicious code in bnpl-blocks-seo-tools (npm)

[email protected] declares itself an SEO tool but on module load (index.js requires./support.js) fetches a platform-specific native binary from one of several Cloudflare Workers hosts (oob-worker.cf100-416.workers.dev, oob-worker.cf103-070.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf99-9b3.workers.dev) with a DNS-TXT-record fallback channel to sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru. The destination hostnames are reconstructed at runtime from split string arrays joined with.join("") to evade static string matching. The fetched binary is written to /tmp or %TEMP% under a disguised name (.cache<hex> on POSIX, dotnet_diag_<hex>.exe on Windows mimicking a.NET diagnostics tool), chmod 0755, and spawned detached with stdio ignored via spawn("/bin/sh") / spawn("cmd"). Execution is gated by a /tmp stamp file for once-per-6h cadence and suppressed when DISABLE_TELEMETRY / ANALYTICS_OPT_OUT / DO_NOT_TRACK are set, reducing detection footprint. The stated package purpose has no relationship to fetching and executing an unsigned native binary.