@ccfly/setup-darwin-x64npm
Advisory published Updated
@ccfly/setup-darwin-x64 is a confirmed malicious npm package (MAL-2026-12313) that executes malicious code on install (malicious versions 0.1.0, 0.1.1, 0.1.3…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in @ccfly/setup-darwin-x64 (npm)
What this malware does
The package ships a prebuilt darwin/x64 Mach-O binary containing a Go agent (module github.com/ccfly/rescue) that, when executed, connects to a hardcoded remote broker at cc.hn / ccfly over WebSocket (ws://ccfly, wss://, https://cc.hn) using github.com/gorilla/websocket, spawns a pseudo-terminal via github.com/creack/pty, and pipes the WebSocket stream into that PTY. Symbols include agent.serve, agent.startPTY, agent.waitAuthorized, agent.wsBase and unixPTY.Read/Write/Resize/Close, giving the remote party interactive shell control of the host. A second stage (setup.downloadCcfly, setup.fetchAndExtract, setup.npmTarballURL, setup.extractFromTarGz, setup.runCcflyInstall, setup.redeemEnrollToken, setup.(*brokerClient).escalateToRescue, with a rodata reference to https://registry.npmjs.org) fetches and executes a further ccfly npm tarball after the broker approves an enrollment token — the additional code executed on the host is chosen by the remote broker, not the installer. The binary also inspects shell RC files and /etc/hosts (setup.scanShellProfilesForProxy, setup.checkProxyResidue, setup.checkHostsResidue, setup.runEnvChecks, setup.envReport) and POSTs an environment report back to the broker (setup.(*brokerClient).post; rodata latest.zshrc, export.ccfly).
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Search your lockfiles and build artifacts for @ccfly/setup-darwin-x64 (11 malicious versions).
If you installed it — respond
Remove @ccfly/setup-darwin-x64 from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If @ccfly/setup-darwin-x64 was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks @ccfly/setup-darwin-x64-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.