MAL-2026-13497 Malicious code in ded-pwa-c-page-maker-props (npm)

On require of the package, compat.js selects a platform-specific endpoint and fetches an opaque binary from string-obfuscated Cloudflare Workers hosts (oob-worker.cf101/cf102/cf103-*.workers.dev, cf99-9b3.workers.dev), writes it to /tmp/.cache<rand> on POSIX or %TEMP%\dotnet_diag_<rand>.exe on Windows, chmods 0755, and spawns it detached via /bin/sh or cmd.exe. Destination hostnames and dropped filenames are assembled from split string arrays joined at runtime, and checks against DISABLE_TELEMETRY/ANALYTICS_OPT_OUT/DO_NOT_TRACK are used as a cover story to gate the drop. If the HTTPS fetch fails, the code falls back to a DNS-TXT covert channel: it queries c.<domain> under *.dl.wel1.ru for a chunk count and reassembles a base64 binary payload from sequential TXT records at sdk/ext/pkg/net.dl.wel1.ru. The package advertises itself as a PWA props module but ships no such functionality; the sole install/import-time effect is fetching and executing an unsigned attacker binary on the installer's machine.