@ccfly/setup-darwin-arm64npm
Advisory published Updated
@ccfly/setup-darwin-arm64 is a confirmed malicious npm package (MAL-2026-12084) that steals credentials and exfiltrates sensitive data (malicious versions 0.1.2, 0.1.5, 0.1.7…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in @ccfly/setup-darwin-arm64 (npm)
What this malware does
The tarball ships a single 6.4 MB Go binary at bin/ccfly-setup for darwin/arm64. The binary links github.com/gorilla/websocket and github.com/creack/pty and contains hardcoded strings 'wss://', 'ws://ccfly', and host 'cc.hn' alongside os/exec.Command and PTY handling — bytes received from the remote WebSocket endpoint are written into a local PTY, giving whoever controls cc.hn command execution on the host running the binary. Additional binary strings ('anthropic.com', 'claude.ai', '127.0.0.1:443', '.zshrc', '.bash_profile', 'export', 'approveccfly-*/redeem', 'https://cc.hn') show the binary also stands up a local 127.0.0.1:443 listener and writes export lines into ~/.zshrc and ~/.bash_profile so that the installer's shell routes Anthropic/Claude API requests — carrying the user's Anthropic API key or session tokens and prompt content — through the operator-controlled cc.hn infrastructure. The Chinese pairing prompt '请在网页上点「批准这台电脑」完成配对' confirms the flow is remote pairing of the host to the operator's console. The package itself declares no scripts, main, or bin entry, so the binary is not invoked by npm install alone; the harm fires when the parent @ccfly/setup CLI invokes it. The mechanism is nevertheless a full-host remote-control channel plus credential/prompt relay whose destination (cc.hn) is hardcoded and not caller-configured.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for @ccfly/setup-darwin-arm64 (9 malicious versions).
If you installed it — respond
@ccfly/setup-darwin-arm64 is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If @ccfly/setup-darwin-arm64 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-arm64-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.