@ccfly/setup-linux-x64npm
Advisory published Updated
@ccfly/setup-linux-x64 is a confirmed malicious npm package (MAL-2026-13418) that opens a backdoor for remote access (malicious versions 0.1.0, 0.1.1, 0.1.2…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in @ccfly/setup-linux-x64 (npm)
What this malware does
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.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Backdoor / remote accessFind it
Search your lockfiles and build artifacts for @ccfly/setup-linux-x64 (10 malicious versions).
If you installed it — respond
@ccfly/setup-linux-x64 establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If @ccfly/setup-linux-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-linux-x64-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.