Guide to Android Penetration Testing

Insecure Android applications pose a warning to users’ privacy and security. Primarily, this kind of app can also result in commercial losses. This is mainly because of the honesty of the Android ecosystem. Cyberattacks on mobile applications are more common than ever. Android penetration testing is one of the finest methodologies to increase safety.

What is Android Penetration Testing?

Finding security damages in an Android application is done through Android penetration testing. It is a methodical way to find flaws in Android apps, ensure their security, and adhere to security regulations. 

• It entails attempting to attack the Android app using various techniques and instruments
• Android penetration testing aims to find and fix app vulnerabilities before cybercriminals exploit them. 
• The security issues are primarily connected to data theft, information drainage, etc.

Benefits of Android Penetration Testing

Some of the key benefits and advantages of Android penetration testing are:

• Uncover security risks of Android apps
• Improve the app efficiency
• Protect sensitive app data fro9m hackers
• Protect application data from other ill-behaving apps
• Prevent reputational loss
• Decrease the cost of the data breach
• Gaining customer trust

Understanding the Architecture of an Android App

An APK file is an archive file; its primary use is to open up the application’s binary files to the end-user. The APK file is an unconnected file from the Android OS. Applications are installed on Android devices through that APK file, installed on the device’s system partition.

• MANIFEST.MF: Contains a list of names/hashes (usually SHA256 in Base64) for all the files of the APK.
• AndroidManifest.xml: A manifest file that describes the application’s package name, activities, resources, version, etc.
• Assets: Contains assets that developers bundle with the application and can be retrieved by the AssetManager. These assets include images, videos, documents, databases, etc.
• lib: Contains native libraries with compiled code for different device architectures.
• res: Contains predefined application resources, like XML files that define a state list of colors, user interface layout, fonts, values, etc. 
• resources.arsc: Contains precompiled resources. It holds information that will link the code to resources.
• classes.dex:  Contains all the java classes in a dex (Dalvik Executable) file format, to be executed by the Android Runtime.

OWASP Mobile Application Security Project

The Open Web Application Security Project (OWASP) is a global welfare firm working to make the web safer. 

The OWASP Mobile Security Project lists the top ten security risks mobile applications face nowadays. Each top mobile security danger is ranked by its threat level and further investigated. Let’s learn each of these in detail:

1. Improper Platform Usage

It is a danger that everyone identifies your platform. This is because it can significantly influence your data or devices. This risk requires the misuse of operating system characteristics or a defeat to use platform security controls properly. 

This may connect Android intents, platform agreements, the Keychain, or other security authorities that are part of the platform.

2. Insecure Data Storage

Data security can be interpreted as the security nearby any stored or transmitted data. Data of Android applications are cached in many locations that needs to be stored securely to shelter data from these attacks.

3. Insecure Communication

 It sends sensitive data over insecure channels. When sending data over non-secure channels, it can be interrupted by anyone who has gained to this channel, anyone on the same network. 

This means that if you are sending critical data, the data can softly be copied. This is very common in public WiFi grant points. When using public WiFi grant points, you should always presume that your data is being intercepted.

4. Insecure Authentication

Authentication is a flow to prove a user’s details to a system. Weak authentication is one of the root causes of most security risks. Attack vectors such as authentication avoidance, information declaration via debug messages, and session invalidation are typical examples of unconfident authentication.

5. Insufficient Cryptography

While cryptography is a basic part of any app that saves user data, there is a common misunderstanding that cryptography can solve all security issues. Cryptography is just a tool that assists in protecting data from attackers. 

An adversary can still access sensitive data if any loose point is found in the cryptographic process. 

6. Insecure Authorization

is a procedure that ensures that only authorized everyone allowed to access the data is producing the access operation. Many mobile applications do not have proper authorization applied due to which low-level users can grant information to any highly privileged user.

7. Client Code Quality

Application code quality is a necessary factor in securing the quality of the final product.. Many security defects can occur in a mobile application, but the most common ones are SQL Injection, Cross-Site Scripting, and Buffer Overflows. The reason why these security defects occur is due to the poor quality of the client code.

8. Code Tampering

It is a procedure in which hackers or attackers exploit the existing master code of an application by adjusting it with malicious payloads, which can lead to business disorder, financial loss, and loss of intellectual property. 

The dispute is usually found in mobile apps downloaded from third-party app stores..

How to Perform Mobile Penetration Testing of Android Applications?

The application penetration testing procedure centers on client-side safety, file system, hardware, and network security. It has long been thought that the end user controls the device.

Stages of the Android App Penetration Testing Methodology

This  is divided into four stages:

1. Discovery needs the pentester to collect data essential for understanding events leading to successfully exploiting mobile applications. Intelligence assembly is the main stage in a penetration test. 

The capacity to disclose secret cues that might shed light on a vulnerability might be the difference between a successful and unsuccessful pentest.

2. Assessment/Analysis entails the penetration tester walking alongside the source code of the mobile application and identifying potential entry points and holes that may be exploited. Analyzing mobile applications is distinct in that the penetration tester must evaluate the applications before and after installation.

3. Exploitation involves the penetration tester manipulating the disclosed vulnerabilities to take dominance of the mobile application in behavior not intended by the programmer from starting did not expect. 

The pentester tries to utilize the vulnerability to steal data or carry out malicious actions and then executes privilege escalation to become the most privileged user (root) and remove all limitations on the activities that may be carried out.

4. Reporting is the final stage of the methodology, and it demands recording and presenting the uncovered issues in a manner that makes sense to management. This is also the stage that modifies a penetration test from an attack. 

A proof of concept must be supplied to validate the results found, the vulnerabilities must be risk-rated, and suitable technical communication must be made for the technical staff.

Android Penetration Testing Tools

Networking Scanning Tools

• Port Scanner: With the help of this program, you can determine which ports are open on a remote computer by scanning its ports using its IP address or domain name. Several more capabilities include protocol recognition, 3G capability, and more.
• Fing: Fing is a specialized network analysis app. You may assess security levels, find intruders, and fix network problems with an easy-to-use interface. It aids you in quickly determining which devices are linked to your Wi-Fi network.
• Network Discovery: Fing and Network Discovery are comparable. It serves as a port scanner for a local area network and is employed for device discovery.
• tPacketCapture: tPacketCapture captures packets without requesting root access. The Android OS’s VpnService is used by tPacketCapture. The external storage saves the captured data in a PCAP file format.

Vulnerability Scanning Tools

• App-Ray: Keep vulnerabilities at bay by using the security scanner by App-Ray. Integrating with EMM-MDM/MAM can check your mobile applications from unknown sources and give them a reputation. The scanner stops you from installing dangerous applications and can identify risks before they damage your data. 
• Quixxi: Quixxi focuses on offering mobile analytics, app security, and revenue loss recovery.
• Qark: With the aid of LinkedIn’s QARK (Quick Android Review Kit), you may identify several Android vulnerabilities in source code and packaged files.
• StaCoAn: StaCoAn is a fantastic tool for static code analysis for mobile applications and is used by developers, ethical hackers, and bug bounty hunters. The lines of code that include API keys, API URLs, hardcoded credentials, decryption keys, coding faults, and other information are examined by this cross-platform tool. 

Exploitation Frameworks

• Metasploit: The most popular open-source penetration testing framework in the world, security experts use Metasploit as a system for penetration testing of Android and as a platform for developing security tools and exploits.  Hundreds of exploits and different payload choices are contained in Metasploit’s vast and comprehensive database.
• Kali Linux:  A Linux distribution used for penetration testing is Kali Linux sophisticated penetration-testing app for Android. Many experts regard this program as the finest for password snipping and injection. 
• Wapiti: An application security tool called Wapiti enables black box testing. Web applications are subjected to black box testing to look for any flaws. Black box testing involves scanning websites and injecting testing data to look for security flaws..

Forensic Tools

• Forensic Analysis for Mobile Apps (FAMA): Framework for Android extraction and analysis that includes an Autopsy Module. Easily extract user data from a device and provide effective reports for Autopsy or outside software.
• Andriller: It is an Android penetration testing app that performs non-destructive, read-only acquisition from Android devices that is forensically sound.
• Autopsy: It is the leading end-to-end open-source platform for digital forensics. An autopsy is a quick, in-depth, and effective hard disc investigation solution developed by Basis Technology with the fundamental features you expect in commercial forensic tools.
• Bandicoot: One uses the Python toolkit to analyze mobile phone metadata. It offers data scientists a full, user-friendly mobile phone metadata analysis environment. Load your datasets, view the data, run the analysis, and export the findings with only a few lines of code.

Best Practices for Android Penetration Testing

1. Observe the security evaluation of your mobile application, then make a plan. 

The penetration analyst must have a thorough understanding of the management of penetration testing. For instance, despite jailbreaking an iPhone appears challenging on paper, it isn’t impossible if you know how. So, if you want to pentest any system, you might need to do a real hack to understand the effects on security. 

Create a plan to get the best results before you start scanning for phone app vulnerabilities. Because the frameworks for each smartphone app vary, you must decide what has to be examined.

2. Knowing about the architecture. 

It’s crucial to comprehend the phone application, how it gathers and manages data in the background, how it interacts with other services and manages user requests, and whether it can detect and react to hacked or root-enabled handsets.

3. Choose relevant Pentesting tools

There are several different mobile vulnerability screening tools currently available. Some may be accessed and downloaded without charge, while others need money. Whatever tool is best will be heavily influenced by the environment in which the application will be used.

Things to remember while performing the test:

• As if the program were a “black box,” try deciphering it. 
• Applications should be used across various networks and service providers, such as 3G, Wi-Fi, and LTE.
• For a quick response, use inbuilt beta testing. 
• Be sure you review the pertinent “app store” requirements as part of the test strategy..

4. Hire a certified penetration tester

After learning everything there is to know about smartphone application penetration testing, it is essential to work with experts. One of the most sought-after credentials for penetration testing employment worldwide is the Certified Penetration Testing certification.

Experts in penetration testing who have personally investigated the market and a variety of tools have developed the course.

5. Include the network and server attack

To scan and identify existing vulnerabilities and attack risks in the system, especially the server hosting the smartphone web apps, pen-testing tools like Nmap and comparable ones are utilized. The testing must also include cross-origin data interchange, open redirect, and unrestricted file upload. 

Attacks that seek to circumvent client-server authentication mechanisms should be considered while evaluating hybrid mobile apps. Implementing web services safety, for instance, might result in XML and XPath injection vulnerabilities.

Future Developments in Android Penetration Testing

Penetration testing will transition from straightforward attack pathways to multi-attack chain scenarios that spill into adversarial emulation over the next ten years, forcing penetration testers to adapt to the threat landscape (Red Team engagements). 

External exploitation will decline due to improved secure coding techniques, active defenses, and oversight. With a sharp rise in phishing to get initial access necessary to pose effect and harm, we have already seen this trend materialize over the previous 5-7 years.