Android Penetration Testing

Android Penetration Testing – Checklist and Tools

Intuitive Android applications have long been the most popular option for users over desktop apps. Custom-built Android application development is one of the most meaningful choices for mobile app developers and business owners, as Android is the globe’s most popular mobile operating system. A cybersecurity expert may also need to hack the smart device to access the OS or a database to pentest the network environment. You can launch hacking tools from an Android device instead of a PC.

Our article will focus on a basic understanding of Android penetration, a carefully curated Android checklist, hacking tools, and other details.

Checklist: Android Pentesting Focus Areas 

A systematic approach to scanning security issues in an Android app, and verifying its security is called Android penetration testing. Here is our checklist to ensure the application abides by security policies.

  1. Data Storage

Testing for data storage in an Android app is a vital part of the process. These tests cover:

  • Sensitive info exposure – tokens or API keys
  • Encryption and Weak cryptograph
  • Checking for Hardcoded credentials
  1. Debug and Error messages

While designing an app, Android developers use various errors or debug messages to comprehend multiple application-level errors. Unfortunately, such error messages are typically left even after production. Hence, malicious actors use these messages to master the flow of the app and its hidden functionalities.

  1. Application-level communication

The communication process of an application with other applications and servers may lead to critical security issues if the interaction between them is not done via a secure channel. Here, cybercriminals use man-in-the-middle attacks to easily intercept communication.

  1. Authentication & Authorization

Key areas to check while performing Android penetration testing are authentication and authorization. These tests cover:

  • Authentication checks on the sensitive endpoint
  • Storage of session token
  • Security issues related to sessions
  • Improper access controls
  1. Code Obfuscation

The procedure of obscuring code to hide its purpose is named code obfuscation. Obfuscation is a method used to protect intellectual property and for anti-tampering. However, it leads to a code that is not easy to reverse engineer. The process is done by adding some meaningless symbols, altering the order of operations, or using various languages.

5 Secure Coding Practices for Android Developers

  1. Communication over HTTPs

HTTPs, ideally, must be standard practice for any company. The only issue with using HTTPs is that it isn’t an option everyone can use. It necessitates modification to your current infrastructure and re-enrollment into your SSL certificate. Now many businesses still don’t use them due to the high cost. Yet, HTTPs will improve your company.

  1. Ask for credentials before showing sensitive data

Secure Android apps use biometric-based authentication, passwords, or data masking to show or display sensitive info such as API Keys.

  1. Sensitive data encryption

Data encryption makes the info unreadable without confidential data, or a key is given only to authorized parties. For example, it protects all the data traveling between two PCs over the Internet or protects hard drive-based data from being altered by malicious programs. 

  1. Use common error messages

As error messages can help attackers reveal hidden functionalities of the application, specialists must use common error messages and get rid of debugging errors or logs once the app is live.

  1. Assess the external data source’s validity 

External storage is used to store application data. That can include your app data, such as records used to run, for instance, a database with a customer list. Therefore, you should ensure that the data stored in external storage has not been corrupted or modified.

What is SSL Pinning?

SSL pinning is used to ensure that the communication between the server and application is encrypted using powerful cryptographic algorithms. The transmission is possible only if the server uses the correct Public Key certificate. SSL pinning prevents the MIM, or man-in-the-middle attack. That is possible when a hacker records the communication between the server and the end-user.

What is Android App Security Project named OWASP?

The OWASP, or Open Web Application Security Project, is a global charitable organization aiming to make the web a safer place. The OWASP project presents a list of the top ten cyber security risks that mobile apps currently face. Let’s explore them in detail:

  • Insecure Data Storage

Data security is the protection surrounding any records stored or transmitted. For example, android application data are stored in locations vulnerable to hacker attacks like servers, mobile devices, and cloud storage.

  • Improper Platform Usage

This threat involves misusing an Android operating system feature or failing to use platform-based security controls properly. That list may include the Keychain, platform permissions, or Android intents.

  • Insecure Authentication

Authentication is a mechanism for proving a user’s identity to a system/process to detect a user’s identity. Weaker authentication, such as authentication bypass, is one of the key causes of many security threats.

  • Insecure Communication

Insecure communication is related to sending sensitive information over non-secure channels. When doing so, it can be intercepted and copied by anybody with access to this channel, like in public WiFi access points.

  • Insufficient Cryptography

Cryptography is a tool to protect user data from attackers, but cryptography cannot deal with all security problems. For example, an adversary can still access sensitive info if any weakness is found in the cryptographic implementation.

  • Client Code Quality

Application code quality is a vital factor in ensuring the quality of the ultimate product. Among many mobile app flaws occurring due to the poor quality of the client code, the typical ones are Cross-Site Scripting, SQL Injection, and Buffer Overflows.

  • Insecure Authorization

A crucial aspect of the CIA triad, authorization ensures that only authorized users are accessing the app. Unfortunately, many mobile applications have incorrect authorization implemented so that low-level users can access the data of a high-privileged user.

  • Code Tampering

Code tampering implies a process in which hackers exploit the application’s source code by altering it with malicious payloads. It may lead to financial loss or loss of intellectual property. The issue occurs in the mobile apps downloaded from risky third-party app stores.

  • Extraneous Functionality

Bad actors like cyber-attackers try to understand the mobile app’s extraneous functionality. The key goal is to find and explore the backend framework’s hidden functionalities.

  • Reverse Engineering

Reverse Engineering is used to decompile the mobile app to get an idea of the application logic. However, code obfuscation prevents attackers from viewing the application code and understanding the logic.

Top 3 Android Pentesting Open-source Tools

Android pentesting is done via a diverse number of tools but let’s see the tools most commonly used:

  1. Apktool: This tool is used for decompiling or reverse engineering any APK file. Using different Linux command lines, Android penetration testers spot sensitive data.
  2. MobSF: This one is an automated, all-in-one mobile app (Windows/iOS/Android) pen-testing, security assessment, and malware analysis framework conducting static and dynamic analysis.
  3. Frida: This dynamic toolkit is used by reverse engineers, app developers, and Android security investigators.

What is Android Penetration Testing?

Android pentesting is detecting security vulnerabilities in an Android app related to info leakage or data theft and fixing them.

An APK file is an archive file separate from the Android OS, and its main use is to distribute the app’s binary files to the end-user. Applications are easily installed on Android devices through the APK file on the gadget’s system partition.

Do Your Assessment

Testing Android apps is similar to testing web applications, yet, many tools and details differ greatly.

Here are some valuable tips to consider when doing your assessment:

  • Check you have the right hardware, like a rooted phone/emulator.
  • Understand the app and enumerate its potential vulnerable points.
  • If the application is not obfuscated, obtain the exact source code.
  • Use tools such as MobSF to assess permission-related vulnerabilities quickly.

Obfuscation won’t make the app irreversible but more complex to hack.

Take your time to explore each tool described here and understand how they work before deciding which one to use. Finally, study the documentation regarding the basic security configurations for properly protecting your application.


What is the timeline for Android pentesting?

The period may vary with the project scope, usually taking 7-10 days to conduct mobile pentesting. The weaknesses start appearing in a pentest dashboard after a couple of days.

Do I get rescans after a vulnerability is fixed?

Yes, users get 2-3 rescans based on the plan. You can use the rescans 30 days from the first scan completion, even if the following vulnerability is fixed.

How much does Android pentesting cost?

The price of Android penetration testing services ranges between $349 and $1499 per scan based on the plan and the number of scans you choose.

Does pen testing differ for a mobile device?

YesMobile pentesting is more complicated than web testing. Besides, the code used for a single environment may be used in other environments due to personalization and various applications.