Objection Android Pentest

Objection Android Pentest Skill

A skill for using Objection to perform runtime exploration and security testing on Android applications.

What Objection Does

Objection is a runtime mobile exploration toolkit powered by Frida. It lets you:

• Bypass security controls (SSL pinning, root detection)
• Hook and inspect methods at runtime
• Explore app internals without decompiling
• Manipulate app behavior dynamically
• Inspect memory, SQLite databases, and more

Important: Objection does NOT bypass jailbreak/root restrictions. You're still limited by the device's sandbox.

Setup

Installation

pip3 install objection

Connection Requirements

1. ADB Connection: Establish a regular ADB connection to the device
2. Frida Server: Start Frida server on the device and verify it's working
3. Target App: Identify the app package name using frida-ps -Uai

Starting Objection

# For rooted devices (specify gadget)
objection --gadget <package.name> explore

# For non-rooted devices
objection explore

Common Workflows

1. Environment Exploration

Gather initial reconnaissance about the app environment:

# View environment variables (may contain passwords, paths)
env

# Get Frida information
frida

2. Security Control Bypass

Disable SSL Pinning

android sslpinning disable

Disable Root Detection

# Disable root detection
android root disable

# Simulate rooted environment (for testing)
android root simulate

3. App Structure Discovery

List Components

# List all activities
android hooking list activities

# List all services
android hooking list services

# List all receivers
android hooking list receivers

Get Current Activity

android hooking get current_activity

Search Classes

# Search for classes by package name
android hooking search classes <package.name>

# List all loaded classes (grows as app is used)
android hooking list classes

Search Methods

# Search methods in a specific class
android hooking search methods <package.name> <ClassName>

# List declared methods with parameters
android hooking list class_methods <package.name>.<ClassName>

4. Method Hooking

Watch a Single Method

android hooking watch class_method <package.name>.<Class>.<method> \
  --dump-args \
  --dump-backtrace \
  --dump-return

Watch an Entire Class

android hooking watch class <package.name>.<Class> \
  --dump-args \
  --dump-return

Warning: Hooking entire classes can crash the application. Use with caution.

Modify Return Values

To force a method to return a specific value:

# Example: Force checkPin() to always return true
android hooking watch class_method <package.name>.<Class>.checkPin \
  --return true

5. Memory Operations

Dump Memory

# Dump all memory
memory dump all <local_destination>

# Dump specific range
memory dump from_base <base_address> <size_to_dump> <local_destination>

List Modules

memory list modules

Search and Write

# Search for patterns
memory search "<hex_pattern>" --string --offsets-only

# Write to memory
memory write "<address>" "<hex_pattern>" --string

6. Class Instances

# Print live instances of a class
android heap print_instances <fully.qualified.ClassName>

7. Keystore and Intents

# List keystore entries
android keystore list

# Launch activities/services
android intents launch_activity
android intent launch_service

8. SQLite Database Access

sqlite
# Interactive SQLite shell

9. File Operations

# Download from device
file download <remote_path> [<local_path>]

# Upload to device
file upload <local_path> [<remote_path>]

10. Screenshots

# Take screenshot
android ui screenshot /tmp/screenshot

# Disable FLAG_SECURE (enables hardware screenshot)
android ui FLAG_SECURE false

11. Shell Commands

android shell_exec <command>

File Transfer

# Import custom Frida script
import <local_path_to_frida_script>

Exit

exit

Best Practices

1. Static Analysis First: Use static analysis to identify targets before dynamic hooking
2. Start Small: Hook individual methods before entire classes
3. Watch for Crashes: Extensive hooking can destabilize the app
4. Document Findings: Keep track of hooked methods and their behavior
5. Use Scripts: For repetitive tasks, create custom Frida scripts

Limitations

• Hooking methods can crash applications (Frida limitation)
• Cannot call instance methods directly on discovered objects
• Cannot create new class instances through Objection
• No built-in crypto method hooking shortcuts

References

• Objection GitHub
• Frida Gadget Documentation
• Modding Mobile Apps with Frida