Bounty Mobile

Mobile bug bounty methodology

1. Get the artifact

Android APK:

# From device
adb shell pm path com.target.app
adb pull /data/app/.../base.apk

# From APKMirror / APKPure (be sure of version match)

iOS IPA: requires jailbroken device or developer build (frida-ios-dump, flexdecrypt).

2. Static analysis (Android)

# Decompile to source
jadx-gui base.apk          # GUI
jadx -d ./out base.apk     # CLI

# Disassemble to smali
apktool d base.apk -o ./out

# Manifest
aapt2 dump badging base.apk
aapt2 dump xmltree base.apk AndroidManifest.xml | head -100

# Quick wins
grep -rE "https?://" ./out/sources/ | sort -u                  # endpoints
grep -rE "(api[_-]?key|secret|token|password)" ./out/sources/   # hardcoded creds
trufflehog filesystem ./out/

Specifically check AndroidManifest.xml for:

• android:exported="true" activities/services/receivers (callable from other apps)
• android:debuggable="true" (massive vuln if shipped)
• Custom URL schemes (<data android:scheme="...">) — deep link attack surface
• Permissions declared (over-privilege?)
• android:allowBackup="true" (backup leakage)
• networkSecurityConfig (cleartext allowed?)

Look at assets/ and res/raw/ for embedded files (often contain SDK keys, dev URLs).

3. Static analysis (iOS)

# IPA is just a ZIP
unzip app.ipa -d app

# Class-dump from binary (if not encrypted)
class-dump-z Payload/MyApp.app/MyApp

# If encrypted (FairPlay) — need decrypted dump from jailbroken device:
# frida-ios-dump or bagbak

# Strings & secrets
strings Payload/MyApp.app/MyApp | grep -E "https?://|api[_-]?key"
trufflehog filesystem Payload/

Inspect Info.plist for:

• LSApplicationQueriesSchemes (URL schemes the app calls)
• CFBundleURLTypes (URL schemes the app accepts) — deep link surface
• NSAppTransportSecurity exceptions (cleartext allowed?)

4. Dynamic — Frida + Objection

# List apps on device
frida-ps -Uai

# Spawn with hook
frida -U -f com.target.app -l hook.js --no-pause

# Objection — high-level wrapper
objection -g com.target.app explore
# Inside objection:
android sslpinning disable
android hooking watch class_method com.target.app.AuthManager.login
android root disable
ios sslpinning disable
ios jailbreak disable

objection covers ~80% of routine instrumentation. Use Frida directly only when you need custom hooks.

5. Cert pinning bypass

After bypass, route traffic through Burp / mitmproxy and replay/edit.

6. IPC / deep-link / intent abuse

For each exported=true activity / service / receiver:

# Trigger directly from adb
adb shell am start -n com.target.app/.SomeActivity --es param "value"
adb shell am broadcast -a com.target.app.ACTION_FOO --es key val

Look for:

• Privilege bypass (activity that should require auth but doesn't check)
• WebView with addJavascriptInterface exposing native methods to JS (XSS → RCE chain)
• File:// URL handling in WebView (read local files)
• Custom URL scheme triggers — e.g. myapp://?action=delete&id=123

ContentProviders: adb shell content query --uri content://com.target.app/... — many leak data.

7. Storage

Check what the app writes to disk (rooted device or post-frida pull):

• /data/data/com.target.app/shared_prefs/ — often plaintext SharedPreferences with tokens
• /data/data/com.target.app/databases/ — SQLite DBs, sometimes with secrets
• External storage (/sdcard/Android/data/com.target.app/) — accessible without root
• iOS: ~/Containers/Data/Application/<UUID>/Library/Preferences/ (plist)

8. Network traffic

# Setup mitmproxy / burp on host, route phone via WiFi proxy
# Install Burp/mitmproxy CA cert as system cert (rooted) or via apk-mitm patch

mitmproxy -p 8080 --mode regular
# or
burpsuite (Pro)

# Capture, intercept, replay, fuzz API calls just like web

After bypass + proxy, the target reduces to a normal API target → use bounty-api skill.

9. Tool stack from this installer (mobile module)

jadx, apktool, aapt2, frida, frida-tools, objection, mobsf, androguard, mitmproxy, apkleaks, apk-mitm.

iOS-specific (less common): class-dump, bagbak, frida-ios-dump, iproxy.

10. Reporting

Show the chain end-to-end: app → exposed component → impact. Include the exact adb command or Frida hook used. Note device + Android version + app version.