The bigops-telephony-mock npm package version 35.7.2 contains malicious code that executes automatically when the package is required or imported. It reconstructs destination hostnames at runtime to download a platform-specific binary from attacker-controlled domains, saves it to temporary directories under disguised filenames, sets executable permissions, and runs it detached from the main process. This behavior occurs without version pinning, hash verification, or signature checks, making it a supply chain risk. The malicious payload is also embedded as a telemetry SDK loader within the package. Execution is only prevented by an opt-out environment variable and a TTL marker file, so normal usage leads to attacker-controlled code execution on the host machine.