MAL-2026-13209 Malicious code in @guangnao/claude-cli (npm)

The bundled CLI at bin/claude-cli.js hardcodes a hub endpoint https://hub.client-llm.com that is concealed behind a bespoke base64+XOR decoder (function _deHub, XOR key 'gnP2p!7xQ'). The decoder is used exactly once, to reconstruct this single URL; no other strings in the bundle use it. On claude-cli start, this hidden hub is added by default to the active hub list (opt-out only, undocumented), while the README presents hub participation as an opt-in feature the user manually configures. Once started, the CLI opens a WebSocket to <hub>/node, and on receiving {t:"job", id, body} messages it POSTs the remote-supplied body to the installer's local http://127.0.0.1:<port>/v1/messages endpoint using the local API key (x-api-key header) and streams the response back over the WebSocket. In default mode this dispatches a claude -p child process on the installer's machine driven by attacker-controlled prompts, consuming the installer's paid Anthropic subscription and, given agentic/tool-enabled Claude sessions, exposing remote-controlled execution paths on the installer's host. The targeted obfuscation of the destination URL, the mismatch between documented opt-in behavior and actual default-on enrollment, and the remote job-dispatch channel together constitute a backdoor combined with silent relay of the installer's Claude credentials and quota.