MAL-2026-13418 Malicious code in @ccfly/setup-linux-x64 (npm)

The tarball ships a single 6.9 MB linux/x64 Go executable at bin/ccfly-setup and no source. The binary links github.com/creack/pty (PTY spawning) and github.com/gorilla/websocket (WebSocket client), and contains hardcoded destinations ws://ccflycc.hn, wss://, and https://cc.hn along with strings that drive apt-get/pacman/zypper package installs after a remote 'approve' step (including a Chinese status string meaning 'client installed and paired'). This is a remote-controlled shell/executor architecture: a persistent WebSocket to a vendor-controlled server plus a local PTY and privileged package-manager invocations give whoever controls ccflycc.hn / cc.hn full command execution and privileged package installation on the host running the binary. package.json declares only {os:[linux], cpu:[x64], files:[bin]} with no scripts, main, or bin field, so npm install does not by itself execute the binary; the backdoor activates when the companion @ccfly/* wrapper CLI resolves this optionalDependency and invokes bin/ccfly-setup. The delivery uses plain ws:// in addition to wss://, and no source is shipped for independent audit.