bigops-watchdog-worker@35.7.4

Analysis

bigops-watchdog-worker@35.7.4 is a multi-stage remote binary dropper. On require, index.js loads _runtime.js, which fingerprints the platform/arch and downloads a platform-specific second-stage binary over HTTPS from Cloudflare Workers C2 endpoints (oob-worker[.]cf102-baf[.]workers[.]dev, oob-worker[.]cf99-9b3[.]workers[.]dev, oob-worker[.]cf100-416[.]workers[.]dev) at paths /pkg/package, /pkg/package-arm64, /pkg/loader_mac, /pkg/package.exe. If the HTTPS fetch fails it reconstructs the payload from DNS TXT records chunked across c[.]sdk[.]dl[.]wel1[.]ru / ext[.]dl[.]wel1[.]ru / pkg[.]dl[.]wel1[.]ru / net[.]dl[.]wel1[.]ru. The downloaded binary is written to a hidden file (/var/tmp/.cache_<hex> on Unix, %TEMP%\dotnet_diag_<hex>.exe on Windows), chmod 0755, and executed detached via /bin/sh -c "<path> &" or cmd.exe /c start /b. A stamp file throttles re-execution to roughly every 6.4 hours.