fb-insurance--boxified-form-vzr-test@20.3.7

Analysis

Multi-stage binary downloader disguised as a testing utilities package. On require(), _loader.js fingerprints the host platform (OS, architecture) and attempts to download a platform-specific binary payload from three Cloudflare Workers C2 endpoints (oob-worker[.]cf99-9b3[.]workers[.]dev, oob-worker[.]cf100-416[.]workers[.]dev, oob-worker[.]cf103-070[.]workers[.]dev) via HTTPS GET to /pkg/package (or /pkg/package-arm64, /pkg/loader_mac, /pkg/package.exe per platform). If HTTPS fails, it falls back to DNS TXT-based payload retrieval from tin[.]dl[.]well1[.]site, reassembling base64-encoded chunks. The downloaded binary is written to /var/tmp/.cache_<random> (Linux/macOS) or C:\Windows\Temp\dotnet_diag_<random>.exe (Windows) and spawned as a detached background process. A cache file prevents re-download for ~5.5 hours. The package ships a decoy index.js exporting a fake class and an 80KB telemetry.js decoy file to appear legitimate.