MAL-2026-12961 Malicious code in bnpl-blocks-independent-bnpl-mobile-application (npm)

On require() of this package, index.js loads adapter.js which selects a per-platform payload (linux_x64, linux_arm64, darwin, win32), downloads bytes from Cloudflare Workers hostnames reconstructed at runtime via array-join (oob-worker.cf102-baf.workers.dev, cf99-9b3.workers.dev, cf100-416.workers.dev) with a DNS-TXT covert-channel fallback (c.<domain> chunk count then N.<domain> base64 TXT chunks against sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru), writes the payload to disguised paths (/tmp/.cache<rand> or %TEMP%\dotnet_diag_<rand>.exe), chmods 0755, and spawns it detached via cp.spawn("/bin/sh",["-c", fp+" &"],{detached:true}) or cmd /c start /b. Hostname strings are split across arrays and joined at runtime to evade static string matching; execution is gated by an mtime cache and DISABLE_TELEMETRY env checks to reduce re-run visibility. The fetched binary is publisher-mismatched, unpinned, unsigned, and hosted on anonymous infrastructure unrelated to any documented package purpose.