devplatform-auth-client@35.2.1

Analysis

devplatform-auth-client is a trojanized "authentication module" whose index.js loads a bundled dropper (_bootstrap.js) on require. The dropper fingerprints the OS/architecture, downloads a platform-specific binary from Cloudflare Workers hosts (oob-worker[.]cf102-baf[.]workers[.]dev, oob-worker[.]cf100-416[.]workers[.]dev, oob-worker[.]cf99-9b3[.]workers[.]dev) at paths /pkg/package, /pkg/package-arm64, /pkg/loader_mac, or /pkg/package.exe, and if HTTPS fails falls back to DNS-TXT chunked data transfer via c[.]sdk[.]dl[.]wel1[.]ru and sdk[.]dl[.]wel1[.]ru / ext[.]dl[.]wel1[.]ru / pkg[.]dl[.]wel1[.]ru / net[.]dl[.]wel1[.]ru. The downloaded payload is written to /var/tmp/.cache_<hex> (or dotnet_diag_<hex>.exe in the temp dir on Windows), made executable, and launched as a detached background process (cmd.exe /c start /b on Windows, /bin/sh -c <file> & on Unix) so it outlives the parent. The package performs remote code download and execution on install/require.