MalwarePublished 6 Aug 2026

@ccfly/setup-linux-x64 (npm) · Malicious Code

Affects @ccfly/setup-linux-x64Source GCVE Database

Malicious package : remove @ccfly/setup-linux-x64 and rotate any secrets on hosts that installed it.

Data as of 6 Aug 2026, 18:33 UTC

Classification

Malicious package

Published to npm · OSV MAL-2026-13418

What to do

Remove @ccfly/setup-linux-x64 from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.

Affected software

Product	Affected	Fixed in
npm@ccfly/setup-linux-x64	Affected 0.1.0 – 0.1.19 10 affected builds	Fixed in–

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Description

The @ccfly/setup-linux-x64 npm package contains a malicious Linux/x64 Go binary that acts as a remote-controlled shell and executor. The binary establishes persistent WebSocket connections to attacker-controlled servers and can execute privileged package manager commands after receiving remote approval. The package does not execute the binary on npm install by itself; activation requires a companion @ccfly wrapper CLI that invokes the binary. No source code is provided for audit, and the binary includes hardcoded command-and-control endpoints. Multiple versions of the package are affected.

Impact

An attacker controlling the command-and-control servers can gain full command execution and privileged package installation capabilities on any host running the binary. This enables remote compromise, persistent backdoor access, and potential system takeover on affected Linux/x64 systems where the binary is invoked. The threat is significant due to the ability to execute arbitrary commands with elevated privileges.

Defensive guidance

Users should avoid installing or invoking the @ccfly/setup-linux-x64 package and its companion @ccfly wrapper CLI. Since the backdoor activates only when the binary is invoked by the wrapper CLI, preventing use of this CLI or removing the package from environments is recommended. Monitor for and remove any instances of this package and related binaries.

Summary

The @ccfly/setup-linux-x64 npm package ships a single 6.9 MB Linux/x64 Go executable without source code. This binary includes functionality for spawning pseudo-terminals and WebSocket clients, connecting to hardcoded attacker-controlled servers (ws://ccflycc.hn, wss://, https://cc.hn). It implements a remote-controlled shell/executor architecture that allows persistent WebSocket communication and privileged package installations via apt-get, pacman, or zypper after a remote 'approve' step. The package.json metadata does not trigger execution on npm install; the backdoor activates only when a companion @ccfly wrapper CLI resolves this optional dependency and invokes the binary. The use of unencrypted ws:// connections and lack of source code prevent independent audit and increase risk.

References

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What to do

Affected software

Description

AI analysisMachine-generated, updated 6 Aug 2026, 18:33 UTC

Technical details

References

Community reviews