MAL-2026-12842 Malicious code in bigops-telephony-ui (npm)

On require of the package, shim.js downloads a platform-specific executable over HTTPS from string-concatenated hostnames (oob-worker.cf100-416.workers.dev, oob-worker.cf101-adfs.workers.dev, oob-worker.cf102-baf.workers.dev) with a DNS-TXT chunked fallback to sdk.dl.wel1.ru and sibling *.dl.wel1.ru subdomains. The retrieved bytes are written to /var/tmp/.cache<hex> on Unix or %TEMP%\dotnet_diag_<hex>.exe on Windows, chmod 0755, and spawned detached via spawn("/bin/sh", ["-c",…]) or spawn("cmd",…). Host strings and the require("child_process") / fs.chmodSync API names are reassembled at runtime via array.join("") to defeat static inspection. The advertised purpose is a React UI component library; nothing about the fetched binary, the decoy filenames, or the anonymous Cloudflare Workers / DNS-fallback delivery matches that stated purpose.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.