MAL-2026-12897 Malicious code in bnpl-blocks-atom-bnpl-store-button-set (npm)

On require() of the package, index.js loads support.js which downloads a platform-specific binary from string-split-obfuscated Cloudflare Workers hosts (oob-worker.cf*.workers.dev) with a DNS TXT fallback under sdk.dl.wel1.ru, writes it to /tmp or %TEMP% under a disguised name such as.cache<hex> or dotnet_diag_<hex>.exe, chmods 0755, and spawns it detached via /bin/sh -c or cmd. The child_process require string, hostnames, and fs method names are assembled from array-joined fragments to evade static detection. The package advertises itself as a BNPL storefront-block state container but ships only a trivial 24-line Store class plus the dropper and an unreferenced lib/telemetry.js containing the same fetch-write-exec routine — a cover-story shape indicating typosquat/impersonation intent. Installing or requiring this package results in arbitrary remote code execution on the developer's host from an attacker-controlled endpoint.