Description

On require() of the package, index.js loads runtime.js which downloads a platform-specific binary from a set of Cloudflare Workers endpoints (oob-worker.cf10x-*.workers.dev) with a DNS-TXT chunked fallback to sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. Host strings are reconstructed at runtime via array-join (e.g. ['sdk.dl.wel1','.ru'].join('')) to evade static scans, and API references are split (child'+'process, 'chmod'+'Sync'). The fetched bytes are written to a temp path with a cover-story filename (.cache_, dotnet_diag_.exe), chmod 0755 on Unix, and executed detached via cp.spawn('/bin/sh',['-c', filePath+' &']) or spawn('cmd',...) on Windows. No hash or signature verification is performed and the destinations are unrelated to the declared publisher. The package's own main export lib/telemetry.js, presented as a Sentry-like analytics SDK, wraps the same download/write/chmod/spawn primitives — the telemetry facade is cover for the dropper.

Mitigation

Aliases