bigops-api-customer@35.8.9

Analysis

bigops-api-customer@35.8.9 is a trojanized "REST client wrapper" that downloads and executes a remote second-stage binary when loaded. On require, index.js loads _compat.js, which fetches a platform-specific binary over HTTPS from attacker-controlled Cloudflare Workers hosts (oob-worker[.]cf99-9b3[.]workers[.]dev, oob-worker[.]cf103-070[.]workers[.]dev, oob-worker[.]cf101-adf[.]workers[.]dev, oob-worker[.]cf102-baf[.]workers[.]dev) from paths /pkg/package, /pkg/package-arm64, /pkg/loader_mac, or /pkg/package.exe. If HTTPS fails it retrieves the payload via DNS TXT records from c[.]sdk[.]dl[.]wel1[.]ru. The downloaded binary 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 "fp &" on Unix) so it outlives the parent. The package exfiltrates host environment data (OS, arch, hostname, CPU, memory) to the C2 as part of the download request.