Pack

Option name: "pack"
Option values: true/false

Requires Eval

The obfuscated code will contain unsafe eval expressions. The code will not work properly in environments that have disabled eval.

Input / Output

This example showcases how Pack transforms the code. Try it out by changing the input code and see changes apply in real-time.

Input.js

// Input.js
// Strict mode JavaScript blocks eval() access to local variables
var myVar = 'Initial Value';
eval(/* @js-confuser-var */ 'myVar' + ' = "Modified Value"');

console.log(myVar); // "Modified Value"

// Output.js
Function(
  'GDSD_L',
  'var uBfgJX="Initial Value";eval("uBfgJX"+" = \\"Modified Value\\"");return console.log(uBfgJX);',
)({});

Bypass Strict Mode

The Pack option is designed to bypass strict mode constraints. This is achieved by wrapping the output code in a Function() call. This allows the code to be executed in a different context, where strict mode is not enforced. Several obfuscation techniques require non-strict mode JavaScript. These include:

Control Flow Flattening (With Statement)
Tamper Protection (Eval scope access)

Usage Example

The provided code example will obfuscate the file input.js and write the output to a file named output.js.

Usage Example

import JSConfuser from "js-confuser";
import {readFileSync, writeFileSync} from "fs";

// Read input code
const sourceCode = readFileSync("input.js", "utf8");
const options = {
  target: 'browser',
  pack: true,
};

JSConfuser.obfuscate(sourceCode, options).then((result)=>{
  // Write output code
  writeFileSync("output.js", result.code);
}).catch(err=>{
  // Error occurred
  console.error(err);  
});

Getting Started

Options

Presets

Requires Eval

Input / Output

Bypass Strict Mode

Usage Example

Enabled In

Requires Eval

​Input / Output

​Bypass Strict Mode

​Usage Example

​Enabled In

Input / Output

Bypass Strict Mode

Usage Example

Enabled In