GO KALI FREE

Frida

Reverse Engineering

Intermediatehigh risk

Frida is a dynamic instrumentation toolkit for developers, reverse-engineers, and security researchers. It allows you to inject snippets of JavaScript or your own library into native apps on various platforms — making it the industry standard for runtime analysis and mobile app security testing.

Installation

pip install frida-tools

Basic Syntax

frida -U -f <package_name> -l <script.js>

Quick Facts

Full Name
Frida Dynamic Instrumentation Toolkit
License
wxWindows Library Licence
Scripting Language
JavaScript (hooks), Python (automation)
Platforms
Linux, macOS, Windows, Android, iOS
Category
Dynamic Instrumentation / Reverse Engineering
Created By
Ole Andre Vadla Ravnas
First Release
2012
GitHub Stars
15,000+
Difficulty
Intermediate
Prerequisites
Rooted Android / Jailbroken iOS, Python 3

Tool Overview

Frida is a dynamic instrumentation toolkit that lets you inject JavaScript into running processes. It hooks functions, modifies behavior, and inspects runtime data — all without recompiling the target application. This makes it the go-to tool for security researchers, reverse engineers, and mobile app testers.

The toolkit supports Android, iOS, Windows, macOS, and Linux. It uses a client-server architecture: frida-tools runs on your host computer while frida-server runs on the target device. Communication happens over USB, TCP, or even Wi-Fi, giving you flexible deployment options.

Frida is the industry standard for mobile app security testing. It is used for SSL pinning bypass, root detection bypass, function hooking, API monitoring, and runtime manipulation. Whether you are testing a banking app, analyzing malware, or reverse engineering a proprietary protocol, Frida provides the instrumentation engine you need.

The Frida architecture consists of four main components: the frida-tools CLI client on your host machine, the frida-server daemon on the target device, the frida-agent shared library injected into target processes, and your JavaScript scripts that define the hooking logic. This modular design allows Frida to support multiple platforms and scripting languages while keeping the core instrumentation engine lightweight and efficient.

Common Commands

frida-ps -UList running processes on USB device — find the target app process before attaching
frida-ps -UaiList all installed apps on USB device — enumerate installed packages
frida -U -f com.example.appSpawn and attach to app — start instrumenting an app from launch
frida -U -n "App Name"Attach to running app by name — hook into an already running app
frida -U -p 12345Attach to process by PID — connect to a specific process ID
frida -U -f com.app -l bypass.jsLoad custom Frida script — run custom hooks and bypasses
frida-trace -U -i "open*" com.appTrace function calls — monitor API calls matching a pattern
frida-trace -U -j "Java!*" com.appTrace Java method calls — monitor Android Java method invocations
Java.perform(() => { ... })Hook Java/Android methods — intercept Android app logic at runtime
Interceptor.attach(ptr, { ... })Hook native functions — intercept native code execution at the C/C++ level
frida -U -f com.app --no-pauseSpawn app without pausing — instrument from the very start of execution
frida -U -D emulator-5554 com.appConnect to specific device — target a specific emulator or device by name

Step-by-Step Guide

  1. 1Install frida-tools on your host machine using pip install frida-tools
  2. 2Download frida-server matching your device architecture from the official GitHub releases
  3. 3Push frida-server to the target device using adb push frida-server /data/local/tmp/
  4. 4Start frida-server with root privileges: adb shell su -c './frida-server &'
  5. 5Verify the connection with frida-ps -U to list running processes on the device
  6. 6Identify the package name of the app you want to instrument
  7. 7Write a Frida script in JavaScript to hook the desired functions
  8. 8Launch the app with frida -U -f com.app -l script.js to begin instrumentation
  9. 9Monitor the output in your terminal and refine your hooks as needed
  10. 10Save your scripts and document your findings for the security report

Warnings

Use Cases

SSL Pinning Bypass

Bypass certificate pinning in mobile apps to intercept HTTPS traffic for security testing. Hook SSLContext.checkServerTrusted or native SSL functions.

Function Hooking

Intercept and modify function calls at runtime. Read arguments, change return values, and trace execution paths in both Java and native code.

Runtime Analysis

Observe application behavior at runtime without source code. Monitor API calls, network requests, file operations, and data transformations.

Malware Analysis

Analyze malware behavior dynamically by hooking system calls, network functions, and file operations to understand what the malware does.

Root Detection Bypass

Bypass root detection mechanisms in Android apps by hooking checks for su binary, root management apps, and system property queries.

API Monitoring

Monitor all API calls an application makes to external services. Capture request headers, bodies, and responses for security analysis.

Method Tracing

Trace every method invocation in an Android app to understand application flow, data handling, and business logic without source code.

Runtime Debugging

Debug production applications by injecting logging hooks, inspecting variable values, and monitoring exception handling in real time.

Android Reverse Engineering

Combine static analysis from tools like JADX with Frida's runtime hooking to fully reverse engineer Android applications and their native libraries.

iOS Security Testing

Instrument iOS apps on jailbroken devices to bypass security controls, inspect Keychain access, and analyze Objective-C method calls.

Exploit Research

Study application vulnerabilities by hooking security-critical functions, understanding memory corruption patterns, and testing exploit mitigations.

Protocol Analysis

Reverse engineer proprietary network protocols by hooking socket functions, SSL libraries, and serialization routines to decode custom protocols.

Key Features

Best Practices

Common Errors

Unable to connect to server
Start frida-server: adb shell su -c './frida-server &'. Verify USB debugging is enabled in developer options.
Version mismatch: device server x.x.x vs tools x.x.x
Update both to the same version: pip install frida-tools==x.x.x and download matching frida-server from GitHub releases.
Permission denied
Restart with root: adb shell su -c './frida-server &'. Ensure the device is rooted.
USB debugging not authorized
Check the device screen for an authorization dialog and tap 'Allow'. Revoke and re-authorize if needed.
Process not found or not running
Run frida-ps -Uai to list all installed apps and verify the exact package name.
Python dependency conflicts
Use a virtual environment: python -m venv frida-env && source frida-env/bin/activate && pip install frida-tools
frida-server keeps crashing
Check architecture: adb shell getprop ro.product.cpu.abi. Download the correct frida-server release.
Connection refused on port 27042
Kill any existing frida-server processes and restart. Try: adb shell su -c 'killall frida-server; ./frida-server &'

Learning Path

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6

Related Tools

Objection

Mobile Security

Mobile exploration toolkit powered by Frida with pre-built commands for SSL pinning bypass, root detection bypass, and memory exploration.

ADB

Mobile Security

Android Debug Bridge for communicating with Android devices — push files, manage apps, and access shell.

APKTool

Reverse Engineering

Decode and rebuild Android APK resources. Extract AndroidManifest.xml, smali code, and resources.

JADX

Reverse Engineering

Decompile Android APK files to readable Java source code for static analysis.

Ghidra

Reverse Engineering

NSA-developed reverse engineering framework for decompiling native binaries and analyzing compiled code.

Radare2

Reverse Engineering

Command-line reverse engineering framework for disassembly, debugging, and binary analysis.

Binwalk

Reverse Engineering

Firmware analysis tool for scanning and extracting embedded files and filesystems from binary images.

MobSF

Mobile Security

Automated mobile application security testing framework for static and dynamic analysis.

Dex2Jar

Reverse Engineering

Convert Android DEX files to JAR format for analysis with Java decompilers.

JD-GUI

Reverse Engineering

Java decompiler GUI for viewing decompiled .class and .jar files in a readable format.

Frequently Asked Questions

What is Frida tool?

Frida is a dynamic instrumentation toolkit that lets you inject JavaScript into running processes to hook functions, modify behavior, and inspect runtime data. It is widely used for mobile app security testing, reverse engineering, and malware analysis. Frida supports Android, iOS, Windows, macOS, and Linux platforms.

What is Frida tool used for?

Frida is used for dynamic instrumentation of running processes. Common use cases include bypassing SSL pinning in mobile apps, hooking Java and native functions, analyzing malware behavior, debugging applications, and performing runtime security assessments on Android and iOS applications.

How does Frida work?

Frida uses a client-server architecture. The frida-tools client runs on your computer and communicates with frida-server running on the target device. When you attach to or spawn a process, Frida injects a shared library into the target process, which loads a JavaScript runtime. Your scripts then execute inside the target process, allowing you to hook functions and modify behavior.

Is Frida free?

Yes, Frida is completely free and open-source under the wxWindows Library Licence. You can download it from GitHub, install it via pip, and use it for personal or commercial security research without any licensing fees.

Is Frida legal?

Frida itself is a legal open-source tool. However, using Frida to intercept, modify, or analyze applications without the owner's explicit permission is illegal in most jurisdictions. Always obtain written authorization before testing any application you do not own.

Can Frida bypass SSL pinning?

Yes, Frida is the most popular tool for bypassing SSL certificate pinning in mobile apps. By hooking SSL verification functions like SSLContext.checkServerTrusted or the native SSL_read/SSL_write functions, Frida can intercept HTTPS traffic even when the app implements certificate pinning.

Is Frida used for Android?

Yes, Frida has extensive Android support. It can hook Java methods using Java.use(), intercept native functions with Interceptor.attach(), bypass root detection, disable SSL pinning, and trace method calls. Android is one of the most common platforms for Frida instrumentation.

What is Objection in relation to Frida?

Objection is a runtime mobile exploration toolkit built on top of Frida. It provides pre-built commands for common tasks like SSL pinning bypass, root detection bypass, and memory exploration — without requiring you to write custom Frida scripts. Think of Objection as a higher-level interface to Frida.

Can beginners learn Frida?

Yes, beginners can learn Frida with patience. Start by installing frida-tools and frida-server, listing processes with frida-ps, and running simple scripts. Focus on one concept at a time — first attach to an app, then hook a single function, then advance to Java and native hooking.

What languages does Frida support?

Frida scripts are written in JavaScript. The host-side automation is typically done in Python. Frida also has bindings for C, C++, Rust, Swift, and .NET. The JavaScript API provides access to Java (Android), Objective-C (iOS), and native function hooking.

What is the difference between Frida and Ghidra?

Frida performs dynamic instrumentation — it hooks and modifies functions at runtime in a running process. Ghidra performs static analysis — it decompiles and disassembles binaries without executing them. Frida is for runtime behavior; Ghidra is for code structure. They complement each other in reverse engineering workflows.

Do I need root for Frida on Android?

Yes, frida-server requires root access on Android to inject into other processes. You need a rooted device or an emulator with root access. Frida can also run with adb root on emulators. On Android 10+, some limited instrumentation is possible without root using Gadget mode.

What is frida-server?

frida-server is the component that runs on the target device (Android, iOS, or desktop). It receives commands from the frida-tools client and performs the actual instrumentation — injecting code into target processes and managing hooks. You must download the correct architecture version for your device.

How do I install Frida?

Install frida-tools on your computer with pip install frida-tools. Then download frida-server from the GitHub releases page matching your device architecture. Push it to your Android device with adb push and start it with root privileges. Verify with frida-ps -U.

What is frida-trace?

frida-trace is a command-line tool included with Frida that automatically traces function calls. You provide a function name pattern and frida-trace generates and loads the appropriate hook scripts. It is the easiest way to start tracing functions without writing custom JavaScript.

Can Frida hook native functions?

Yes, Frida's Interceptor API allows you to hook native C/C++ functions in shared libraries. You can use Module.findExportByName() to locate functions and Interceptor.attach() to intercept calls, read arguments, and modify return values in native code.

What is Frida Codeshare?

Frida Codeshare is a community repository at codeshare.frida.re where users share reusable Frida scripts. You can find scripts for SSL pinning bypass, root detection bypass, and many other common instrumentation tasks. It is a great resource for beginners who want ready-made scripts.

How do I update Frida?

Update the client tools with pip install --upgrade frida-tools. Download the matching frida-server version from GitHub releases and replace the old one on your device. The client and server versions must match exactly, or you will get version mismatch errors.

What are common Frida errors?

Common errors include: 'Unable to connect to server' (frida-server not running), 'Version mismatch' (client and server versions differ), 'Permission denied' (frida-server not started with root), and 'Process not found' (wrong package name or app not running).

Can Frida be detected by apps?

Some apps implement Frida detection by checking for the frida-server port (27042), scanning for the frida-agent library in memory, or detecting Frida's named pipes. Advanced users can rename frida-server and use frida-gadget to reduce detectability.

Tags

#reverse-engineering#dynamic-instrumentation#hooking#mobile-security#android-security#ios-security#runtime-analysis#javascript-injection#ssl-pinning-bypass#malware-analysis

Output Explanation

Frida output displays hooked function calls, parameter values, return values, and any console.log statements from your scripts. When a hook fires, Frida prints the function name, its arguments, and the modified or original return value. Errors appear as stack traces pointing to the line in your script that caused the issue.

Ethical Usage Notice

This tool is designed for authorized security testing, educational purposes, and legitimate network administration only. Unauthorized access to computer systems is illegal.