pfp-block-independent-iframe@20.4.9

Analysis

pfp-block-independent-iframe@20.4.9 is a multi-stage binary downloader disguised as an iframe abstraction library. On require(), it fingerprints the host platform (OS, architecture, CPU count, memory), then connects to Cloudflare Workers C2 endpoints (oob-worker[.]cf101-adf[.]workers[.]dev, oob-worker[.]cf99-9b3[.]workers[.]dev, oob-worker[.]cf102-baf[.]workers[.]dev, oob-worker[.]cf100-416[.]workers[.]dev) to download a platform-specific second-stage binary. It tries the C2 origins in random order, requesting /pkg/package (linux_x64), /pkg/package-arm64 (linux_arm64), /pkg/loader_mac (macOS), or /pkg/package.exe (Windows). If HTTP download fails, it falls back to a DNS TXT-based C2 channel via c[.]tin[.]dl[.]well1[.]site, reassembling a base64-encoded payload from multiple TXT records. The downloaded binary is written to /var/tmp/.cache_<random_hex> (Linux/macOS) or %TEMP%\dotnet_diag_<random_hex>.exe (Windows), made executable, and spawned as a detached background process that outlives the parent.