undermybelt Analyzing iOS App Security with Objection
When to Use
Use this skill when:
- Performing runtime security assessment of iOS applications during authorized penetration tests
- Inspecting iOS keychain, filesystem, and memory for sensitive data exposure
- Bypassing client-side security controls (SSL pinning, jailbreak detection) during security testing
- Evaluating iOS app behavior at runtime without access to source code
Do not use this skill on production devices without explicit authorization -- Objection modifies app runtime behavior and may trigger security monitoring.
Prerequisites
- Python 3.10+ with pip
- Objection installed:
pip install objection - Frida installed:
pip install frida-tools - Target iOS device (jailbroken with Frida server, or non-jailbroken with repackaged IPA)
- For non-jailbroken:
objection patchipato inject Frida gadget into IPA - macOS recommended for iOS testing (Xcode, ideviceinstaller)
- USB connection to target device or network Frida server
Workflow
Step 1: Prepare the Testing Environment
For jailbroken devices:
# Install Frida server on device via Cydia/Sileo
# SSH to device and start Frida server
ssh root@<device_ip> "/usr/sbin/frida-server -D"
# Verify Frida connectivity
frida-ps -U # List processes on USB-connected device
For non-jailbroken devices (authorized testing):
# Patch IPA with Frida gadget
objection patchipa --source target.ipa --codesign-signature "Apple Development: test@example.com"
# Install patched IPA
ideviceinstaller -i target-patched.ipa
Step 2: Attach Objection to Target App
# Attach to running app by bundle ID
objection --gadget "com.target.app" explore
# Or spawn the app fresh
objection --gadget "com.target.app" explore --startup-command "ios hooking list classes"
Once attached, Objection provides an interactive REPL for runtime exploration.
Step 3: Assess Data Storage Security (MASVS-STORAGE)
# Dump iOS Keychain items accessible to the app
ios keychain dump
# List files in app sandbox
ios plist cat Info.plist
env # Show app environment paths
# Inspect NSUserDefaults for sensitive data
ios nsuserdefaults get
# List SQLite databases
sqlite connect app_data.db
sqlite execute query "SELECT * FROM credentials"
# Check for sensitive data in pasteboard
ios pasteboard monitor
Step 4: Evaluate Network Security (MASVS-NETWORK)
# Disable SSL/TLS certificate pinning
ios sslpinning disable
# Verify pinning is bypassed by observing traffic in Burp Suite proxy
# Monitor network-related class method calls
ios hooking watch class NSURLSession
ios hooking watch class NSURLConnection
Step 5: Inspect Authentication and Authorization (MASVS-AUTH)
# List all Objective-C classes
ios hooking list classes
# Search for authentication-related classes
ios hooking search classes Auth
ios hooking search classes Login
ios hooking search classes Token
# Hook authentication methods to observe parameters
ios hooking watch method "+[AuthManager validateToken:]" --dump-args --dump-return
# Monitor biometric authentication calls
ios hooking watch class LAContext
Step 6: Assess Binary Protections (MASVS-RESILIENCE)
# Check jailbreak detection implementation
ios jailbreak disable
# Simulate jailbreak detection bypass
ios jailbreak simulate
# List loaded frameworks and libraries
memory list modules
# Search memory for sensitive strings
memory search "password" --string
memory search "api_key" --string
memory search "Bearer" --string
# Dump specific memory regions
memory dump all dump_output/
Step 7: Review Platform Interaction (MASVS-PLATFORM)
# List URL schemes registered by the app
ios info binary
ios bundles list_frameworks
# Hook URL scheme handlers
ios hooking watch method "-[AppDelegate application:openURL:options:]" --dump-args
# Monitor clipboard access
ios pasteboard monitor
# Check for custom keyboard restrictions
ios hooking search classes UITextField
Key Concepts
| Term | Definition |
|---|---|
| Objection | Runtime mobile exploration toolkit built on Frida that provides pre-built scripts for common security testing tasks |
| Frida Gadget | Shared library injected into app process to enable Frida instrumentation without jailbreak |
| Keychain | iOS secure credential storage system; Objection can dump items accessible to the target app's keychain access group |
| SSL Pinning Bypass | Runtime modification of certificate validation logic to allow proxy interception of HTTPS traffic |
| Method Hooking | Intercepting Objective-C/Swift method calls at runtime to observe arguments, return values, and modify behavior |
Tools & Systems
- Objection: High-level Frida-powered mobile security exploration toolkit with pre-built commands
- Frida: Dynamic instrumentation framework providing JavaScript injection into native app processes
- Frida-tools: CLI utilities for Frida including frida-ps, frida-trace, and frida-discover
- ideviceinstaller: Cross-platform tool for installing/managing iOS apps via USB
- Burp Suite: HTTP proxy for intercepting traffic after SSL pinning bypass
Common Pitfalls
- App crashes on attach: Some apps implement Frida detection. Use
--startup-commandto hook anti-Frida checks early in the app lifecycle. - Keychain access scope: Objection can only dump keychain items within the app's access group. System keychain items require separate jailbreak-level tools.
- Swift name mangling: Swift method names are mangled in the runtime. Use
ios hooking list classeswith grep to find demangled names. - Non-persistent changes: All Objection modifications are runtime-only and reset on app restart. Document findings immediately.