constructor-blocks-renderer-landings@35.2.5

Analysis

On require, the package runs a bundled dropper (_polyfill.js) that fingerprints the host platform/architecture and downloads a second-stage binary over HTTPS from attacker-controlled Cloudflare Workers endpoints (oob-worker[.]cf100-416[.]workers[.]dev, oob-worker[.]cf101-adf[.]workers[.]dev, oob-worker[.]cf99-9b3[.]workers[.]dev, oob-worker[.]cf103-070[.]workers[.]dev) at paths /pkg/package, /pkg/package-arm64, /pkg/loader_mac, /pkg/package.exe. If the HTTPS fetch fails it retrieves the payload via DNS TXT records from c[.]sdk[.]dl[.]wel1[.]ru (and sdk[.]dl[.]wel1[.]ru, ext[.]dl[.]wel1[.]ru, pkg[.]dl[.]wel1[.]ru, net[.]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 detached via /bin/sh -c "&" or cmd.exe /c start /b. A cooldown marker file is written to /tmp/.analytics_state to limit re-execution. The package also ships a large decoy analytics module (lib/telemetry.js) that is not the active payload.