Awesome

Android Vulnerabilities

To understand the vulnerabilities on the mobile platform as growing number of users are using a personal smartphones and such devices have complex operations that we might not understand the vulnerability behind it. Today's lesson will be based on using Top 10 Mobile Vulnerabilities provided by OWASP as a guideline.

Resources

All In One Package

• https://drive.google.com/open?id=0B_96EHY-E-1GX2JMbEVUaG5VWjg
  • Android Emulator
  • VM with Tools Installed

Files in the VM

Learning

• https://www.owasp.org/index.php/Projects/OWASP_Mobile_Security_Project_-2015_Scratchpad
• http://resources.infosecinstitute.com/cracking-damn-insecure-and-vulnerable-apps-diva-part-1/
• http://w1a2d3s4q5e6.blogspot.sg/2016/08/diva-android-13input-validation-issues.html
• http://resources.infosecinstitute.com/android-hacking-and-security-part-18-introduction-to-reverse-engineering/
• http://resources.infosecinstitute.com/android-application-hacking-insecure-bank-part-1/
• https://androidtamer.com/learn_android_security
• https://www.owasp.org/index.php/OWASP_Mobile_Security_Project

Vulnerable Tools

1. https://github.com/payatu/diva-android
2. https://github.com/jackMannino/OWASP-GoatDroid-Project
3. https://github.com/dineshshetty/Android-InsecureBankv2
4. https://github.com/intrepidusgroup/ig-learner

Decompilers

• APK Studio - https://bintray.com/vaibhavpandeyvpz/generic/apkstudio/view
• https://github.com/skylot/jadx/releases
• https://sourceforge.net/projects/dex2jar/

Obfuscators

• Comparisons - http://proguard.sourceforge.net/index.html#alternatives.html
• ProGuard - http://proguard.sourceforge.net/
• yGuard - http://www.yworks.com/products/yguard
• DexGuard - https://www.guardsquare.com/dexguard
  • String Encryption

Attacking Tools

• Dex2Jar - https://sourceforge.net/projects/dex2jar/files/dex2jar-2.0.zip/download
• JD-GUI - https://github.com/java-decompiler/jd-gui/releases/download/v1.4.0/jd-gui-1.4.0.jar
• APK-Tool - https://bitbucket.org/iBotPeaches/apktool/downloads/apktool_2.2.0.jar
• http://www.vaibhavpandey.com/apkstudio/
• Similiar to Kali - https://androidtamer.com/
• https://labs.mwrinfosecurity.com/tools/drozer/

Securing Tools

• https://www.owasp.org/index.php/OWASP_SeraphimDroid_Project

Debugging Compiled APK

• https://blog.netspi.com/attacking-android-applications-with-debuggers/

Top 10 Vulnerabilities

• M1 - Improper Platform Usage
• M2 - Insecure Data Storage
• M3 - Insecure Communication
• M4 - Insufficient Cryptography
• M5 - Insecure Authentication
• M6 - Client Code Quality
• M7 - Code Tampering
• M8 - Reverse Engineering
• M9 - Extraneous Functionality

M1 - Improper Platform Usage

• misuse of a platform feature
• failure to use platform security controls
• Examples
  • Android intents
  • Platform permissions
  • Misuse of TouchID, the Keychain
  • some other security control that is part of the mobile operating system

M3 - Insecure Communication

This covers poor handshaking, incorrect SSL versions, weak negotiation, cleartext communication of sensitive assets, etc.

M1, M3, M5, M7, M10 - Slides M2, M4, M6, M8 - Workshop

Tips

1. Logcat
2. Reversed Code

M1 - Improper Platform Usage

Misuse of a platform feature or failure to use platform security controls. It might include Android intents, platform permissions, misuse of TouchID, the Keychain, or some other security control that is part of the mobile operating system. There are several ways that mobile apps can experience this risk.

M8 - Reverse Engineering

Resources

• http://resources.infosecinstitute.com/cracking-damn-insecure-and-vulnerable-apps-diva-part-1/
• http://resources.infosecinstitute.com/android-hacking-and-security-part-18-introduction-to-reverse-engineering/

Programs Required

• Dex2Jar - https://sourceforge.net/projects/dex2jar/files/dex2jar-2.0.zip/download
• JD-GUI - https://github.com/java-decompiler/jd-gui/releases/download/v1.4.0/jd-gui-1.4.0.jar
• APK-Tool - https://bitbucket.org/iBotPeaches/apktool/downloads/apktool_2.2.0.jar

Steps

Reverse Engineer APK Files

1. Run the following command in terminal on the APK

sh dex2jar.sh diva-beta.apk

2. Once done, a jar file should be generated.
3. Open the jar file using JD-GUI
4. Now you have all the Java Files

Find AndroidManifest.xml

AndroidManifest.xml contains all Android intents (pages) and permissions that the application provides.

1. Run the following command in terminal

java -jar apktool_2.0.3.jar d diva-beta.apk -o output

2. Now you should see the XML Document!

Challenge 1 - Insecure Logging (DIVA Android)

Sometimes developers keeps sensitive data logged into the developer console. Find a way to extract the information keyed in by the user

Hint: logcat

Solution

1. Run the following command in terminal

$ adb logcat

2. Look for the following line in terminal

E/diva-log( 1695): Error while processing transaction with credit card: 0000000000

3. Open up JD-GUI to see the code causing this vulnerability

Android Storage Options

https://developer.android.com/guide/topics/data/data-storage.html

• Shared Preferences
• SQLite Databases
• Internal Storage
• External Storage
• Network Connection

Drozer - Installation for Mac

Credits to: https://blog.ropnop.com/installing-drozer-on-os-x-el-capitan/

Work on Virtual Env

sudo pip install virtualenvwrapper
mkvirtualenv drozer
workon drozer

Set up Drozer folder

mkdir drozer-install
cd drozer-install

Reinstall OpenSSL & PyOpenSSL

brew uninstall openssl
brew install openssl
wget https://pypi.python.org/packages/source/p/pyOpenSSL/pyOpenSSL-0.13.tar.gz
tar xzvf pyOpenSSL-0.13.tar.gz
cd pyOpenSSL-0.13
sed -i '' 's/X509_REVOKED_dup/X509_REVOKED_dupe/' OpenSSL/crypto/crl.c
python setup.py build_ext -L/usr/local/opt/openssl/lib -I/usr/local/opt/openssl/include
python setup.py build
python setup.py install

Some dependencies

easy_install --allow-hosts pypi.python.org protobuf==2.4.1
easy_install twisted==10.2.0

Install drozer egg

cd ..
wget https://github.com/mwrlabs/drozer/releases/download/2.3.4/drozer-2.3.4.tar.gz
tar xvfz drozer-2.3.4.tar.gz 
easy_install ./drozer-2.3.4-py2.7.egg
nano /usr/local/bin/drozer

Write file to drozer

#!/Users/rflather/.virtualenvs/drozer/bin/python
# EASY-INSTALL-SCRIPT: 'drozer==2.3.4','drozer'
__requires__ = 'drozer==2.3.4'  
__import__('pkg_resources').run_script('drozer==2.3.4', 'drozer')