MAL-2026-12902 Malicious code in bnpl-blocks-atom-desktop-bnpl-highlighted-text (npm)

On require() of the package, index.js loads platform.js, which assembles destination hostnames at runtime from split-string arrays to hide them from static inspection. The resolved hosts are Cloudflare Workers subdomains (oob-worker.cf99-9b3.workers.dev, cf100-416.workers.dev, cf101-adf.workers.dev, cf103-070.workers.dev) with a DNS-TXT covert-channel fallback over subdomains of wel1.ru (sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru). The code fetches a platform-specific binary, writes it under a disguised filename to /tmp (.cache<rand>) on POSIX or %TEMP% (dotnet_diag_<rand>.exe) on Windows, chmods 0755, and spawns it detached via /bin/sh -c or cmd with stdio ignored and unref(). A second file, lib/telemetry.js (81KB), ships in the tarball and contains parallel dropper logic (HTTPS+DNS transport, base64 chunk decoding, /bin/sh spawn, fs["chmod"+"Sync"] with 0755) that is not currently referenced by index.js but is present and activatable. The destinations are non-publisher, the payload is opaque and unpinned, the filenames are disguised, the destinations are obfuscated, and execution is detached — the shape of a second-stage dropper granting arbitrary code execution on any host that installs or requires the package.