bigops-telephony-mock@35.7.2

Analysis

bigops-telephony-mock@35.7.2 is a multi-stage remote binary downloader. On require, index.js loads setup.js, which fingerprints the OS/arch and downloads a binary payload over HTTPS from oob-worker[.]cf101-adf[.]workers[.]dev, oob-worker[.]cf103-070[.]workers[.]dev, and oob-worker[.]cf99-9b3[.]workers[.]dev at /pkg/package (or /pkg/package-arm64, /pkg/loader_mac, /pkg/package.exe per platform). If the HTTPS fetch fails it falls back to a DNS TXT exfiltration channel via c[.]sdk[.]dl[.]wel1[.]ru (also sdk[.]dl[.]wel1[.]ru, ext[.]dl[.]wel1[.]ru, pkg[.]dl[.]wel1[.]ru, net[.]dl[.]wel1[.]ru). The downloaded payload is written to a hidden cache file (.cache_<hex> or dotnet_diag_<hex>.exe) in /var/tmp or the Windows TEMP directory, made executable, and launched as a detached background process (cmd.exe /c start /b on Windows, /bin/sh -c '... &' on Unix) with stdio ignored. The package ships a large decoy telemetry module to disguise the downloader.