🛡️ MAL-2026-12037 — bigops-create-manifest

Malicious code in bigops-create-manifest (npm)

Source: amazon-inspector

On require, index.js loads _polyfill.js which selects a platform-specific endpoint, downloads an opaque native binary over HTTPS from one of several Cloudflare Workers hosts (oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev), with a DNS TXT covert-channel fallback that reads base64-encoded chunks from sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru. The fetched bytes are written to a randomized filename disguised as dotnet_diag_<hex>.exe on Windows or.cache_<hex> under /var/tmp on Unix, chmod 0755, and spawned detached via /bin/sh -c or cmd. C2 hostnames and resolver domains are assembled at runtime via split-string array joins; artifact naming, an analytics_state marker, and DISABLE_TELEMETRY env checks frame the operation as diagnostics. The package's advertised purpose (a manifest wrapper) has no need for downloading and executing a native binary from third-party infrastructure.