statist-browser-typed-client-rubliq.platform.keycloak @20.2.5

Summary

The package presents itself as a Keycloak typed client but on require() executes a binary dropper. index.js loads _adapter.js, which reconstructs destination hostnames from split string fragments joined via.join('') to hide them from static analysis, selects a platform-specific URL, and downloads a binary over HTTPS from Cloudflare Workers hosts (oob-worker.cf101-adf.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf102-baf.workers.dev). The downloaded bytes are written to /tmp or the Windows Temp directory under disguised names (.analytics_state, dotnet_diag_*.exe,.cache_*), chmodded to 0755, and spawned detached via /bin/sh -c '<path> &' or cmd.exe /c start. A DNS-TXT covert-channel fallback under subdomains of dl.well1.site (tin.dl.well1.site, tina.dl.well1.site, ldr.dl.well1.site, win.dl.well1.site) reassembles a base64-encoded binary from TXT record chunks when HTTPS fetch fails, feeding the same write+chmod+spawn chain. The child_process module name is constructed as require('child_' + 'process') and chmodSync is accessed as fs['chmod'+'Sync'] to further evade pattern matching. Environment variables DISABLE_TELEMETRY, ANALYTICS_OPT_OUT, and DO_NOT_TRACK are checked to give the behavior a telemetry cover story. lib/telemetry.js contains a parallel dropper implementation with the same primitives, wrapped in 'Analytics SDK' comments. The package name resembles a legitimate Keycloak client but the shipped code performs installer-side arbitrary code execution rather than any Keycloak functionality.

Source: amazon-inspector (fc008dc0448aacf1e76c6111e7644f91d077009d358a0085be46166e92ce59cf)