MSTG (Mobile Security Testing Guide)

The MSTG (i.e., the Mobile Security Testing Guide) is a comprehensive tool that offers information and guidance about mobile application security.

The MSTG (aka the Mobile Security Testing Guide) is a project of the Open Web Application Security Project. The OWASP mobile security testing guide is a comprehensive tool that offers information and guidance about mobile application security. It is designed to help mobile application developers, testers, and security professionals better understand and deal with security issues.

This guide includes information on testing mobile security for both Android and iOS. The guide provides information about common security vulnerabilities, mobile app risks, and recommended testing methods and tools.

The MSTG covers a wide range of topics, including:

  • Mobile App Security Overview: This overview introduces the concepts of mobile app security and common threats.
  • Security Considerations for Mobile App Architecture: This article discusses security issues related to the design of mobile apps.
  • Platform-Specific Security Concerns: This section addresses specific security issues for Android and iOS.
  • Network Security: This covers issues related to data transfer and communication between mobile applications and servers.
  • Authentication & Authorization: This article discusses the best practices to implement secure authentication and authorization mechanisms in mobile apps.
  • Data Storage Security: Secure storage of sensitive data is addressed on mobile devices.
  • Platform Interaction: This section covers security issues when mobile apps interact or communicate with the platform.
  • Resiliency Against Reverse Engineering and Tampering: This article discusses techniques for protecting mobile apps from reverse engineering and tampering.
  • Privacy: This section covers privacy issues and the best practices to handle user data.
  • Mobile Threat Model: Creates a model of potential security threats for mobile applications.

How Does the MSTG Improve Mobile Security?

The Mobile Security Testing Guide (MSTG), in many ways, contributes to mobile security improvement:

  • Education and Awareness: MSTG offers comprehensive and current information about mobile application security. It helps security professionals, developers, and testers become more aware of the risks and challenges of mobile security by guiding common vulnerabilities and security considerations.
  • Standardized Testing: This guide outlines standardized methodologies for testing the security of mobile apps. The consistency of testing methods allows for more reliable and effective security assessments on different mobile platforms.
  • Identification of Common Vulnerabilities: The MSTG highlights mobile app security risks and vulnerabilities. Understanding these issues allows developers and security teams to address them proactively during the development cycle, reducing the risk of security breaches.
  • Practical Guidance and Recommendations: This guide offers practical recommendations for implementing security measures within mobile applications. This practical guide helps developers implement secure coding, data storage, and robust authentication mechanisms.
  • Platform-Specific Considerations: The MSTG recognizes that Android and iOS have different security concerns. The MSTG ensures that the security testing is tailored for each mobile operating system.
  • Privacy Emphasis: Mobile applications are often used to handle sensitive data from users. The MSTG puts a lot of emphasis on privacy issues. The MSTG has developed guidelines to ensure that user data is dealt with responsibly and users’ privacy is protected.
  • Threat Modeling: By including a section on mobile threat modeling, organizations are encouraged to consider threats that could affect their mobile applications. This proactive approach assists in identifying security risks and mitigating them early in the development cycle.
  • Open Source and Community Collaboration: The MSTG is an OWASP-sponsored project and benefits from the community’s collaboration and contributions. Open-source guides allow security professionals around the globe to contribute their knowledge, share their expertise, and make improvements to the guide.
  • Adaptability to Evolving Threats: Mobile security challenges evolve. The MSTG was designed to keep up with these changes. The MSTG is updated regularly, and the community’s contributions remain current.

The Mobile Security Testing Guide is a valuable tool for improving mobile security. It provides educational resources, standardizes testing methods, offers practical guidance, and fosters a collaborative effort among the community to combat the dynamic nature of mobile security threats.

Standardized Testing Methodologies Used by the MSTG

The Mobile Security Testing Guide outlines standard testing methodologies for assessing the security of mobile apps. These methodologies offer a structured way for security professionals, testers, and developers to identify and fix potential vulnerabilities. These are the principal testing methodologies used by the MSTG.

  • Security Architecture Review: This review evaluates the overall security architecture of the mobile application. It checks how security controls have been implemented and integrated into the structure of the mobile application.
  • Static Analysis: Analyzes an application’s source code (bytecode or binary) without executing it. It identifies security vulnerabilities such as hardcoded secrets and insecure coding.
  • Dynamic Analysis: This involves interacting with an application running to evaluate its behavior in real-world situations. It identifies vulnerabilities at runtime, such as unsecured data transmission or inadequate session management.
  • Network Security Testing: Tests data transfer security between mobile apps and servers. This tests encryption and secure communication protocols.
  • Authentication Testing: This test evaluates the effectiveness and efficiency of the authentication mechanisms implemented in mobile applications—tests to identify common vulnerabilities in authentication, including weak passwords and credential storage.
  • Authorization Testing: Verifies that the application restricts access to data and functionalities based on users’ roles and permissions. These tests are performed to identify authorization vulnerabilities such as insecure object references (IDOR) or privilege escalation.
  • Data Storage Test: This test evaluates the security of the data storage mechanisms in the mobile device. Secure storage of sensitive data, protection against leakage, and resistance to data manipulation are all checked.
  • Platform Interaction Test: This test evaluates how the mobile app interacts and communicates with the platform. It identifies security risks related to inter-app communication, platform-specific features, and other aspects.
  • Reverse Engineering and Code Tampering Resistance Testing: Tests mobile apps’ resistance to reverse engineering and code tampering. These test the effectiveness and efficiency of anti-reverse engineering measures.
  • Privacy Testing: This test examines how an application treats user data and if it respects the privacy of users. Privacy-related vulnerabilities are identified, and compliance with privacy regulations is ensured.
  • Mobile Threat Model: Create a threat model specific to your mobile application. It identifies possible threats, attack vectors, and security controls to reduce risks.

These standard testing methodologies ensure a thorough, systematic assessment of the security of mobile applications. They cover various aspects of design, implementation, and runtime behavior. Security professionals can use these methodologies to perform comprehensive security testing, identify vulnerabilities, and address them in a structured way.


The Mobile Security Testing Guide is a valuable tool that developers can use to enhance the security and stability of their mobile apps throughout the entire development lifecycle. Here’s how developers should use the MSTG effectively:

  • Educational Resource: Developers can use MSTG to learn about mobile application security. The guide contains educational content on security risks, vulnerabilities, and best practices.
  • Secure Coding Practices: MSTG guides secure coding for mobile development. Developers can use these recommendations to ensure security is integrated into the development phase.
  • Design Considerations: MSTG addresses security issues in the design and architecture of mobile applications. Developers can use the information in this document to make informed choices about security features and controls they want to implement in their applications.
  • Threat Modeling: Developers can employ the threat modeling guidance provided by the MSTG to identify potential security threats and vulnerabilities early in the development process. This proactive approach helps to design robust security controls.
  • Testing Guidance: MSTG provides standardized methodologies for security assessments. Developers can use these methodologies to test their security applications, identifying and addressing any vulnerabilities before deployment.
  • Code Reviews: During code review, developers can use MSTG to check their code for common security pitfalls. Reviews will ensure that the code is aligned with best practices and help to catch security issues before they are part of the production code.
  • Integration with Development Tools: Developers can integrate MSTG Guidelines into their development tools. Integration could involve using static analysis to check code against secure standards or incorporating dynamic analyses to test runtime behavior.
  • Platform-Specific Security Considerations: MSTG provides information about security considerations specific to Android and iOS. Developers can use the information provided to address platform-specific challenges in their applications.
  • Privacy Compliance: The MSTG contains guidance on privacy concerns. Developers can use these guidelines to ensure their applications comply with privacy regulations and handle user data responsibly.
  • Continuous Improvement: MSTG can be used as a reference by developers to improve continuously. As security threats change, developers can keep up to date with the latest security practices and updates in the guide, allowing them to adapt their development processes accordingly.
  • Community Engagement: Developers are encouraged to engage actively in the MSTG community. They can participate in discussions and share their experience. This collaborative approach helps to refine and update the guide to address emerging security issues.

By incorporating the MSTG’s principles, recommendations, and testing methodologies, developers can improve the security posture of mobile applications. MSTG can reduce the risk of security breaches and better protect user data.

How MSTG Improves the User Experience

The Mobile Security Testing Guide (MSTG), while primarily focused on improving the security and usability of mobile applications, can indirectly contribute to an improved user experience. 

Here’s how MSTG impacts user experience:

  • Data Protection and Privacy: Following the MSTG guidelines, developers can implement robust data security measures and respect users’ privacy. Users are more likely to have a positive user experience when they know their sensitive data is handled securely in compliance with privacy laws.
  • App Stability and Reliability: Security measures, such as secure code practices and thorough testing of vulnerabilities, recommended by MSTG can contribute to overall stability and reliability. Users appreciate apps that are reliable and less likely to crash or behave unexpectedly.
  • Protection Against Data Breaches: Implementing MSTG’s security best practices help protect user data against unauthorized access and data breaches. Users are more satisfied with applications that prioritize the security of personal information.
  • Resilience Against Tampering: MSTG offers guidance on making mobile apps more resistant to reverse engineering and tampering. When users believe that the integrity of an app has been protected, they are more likely to have a favorable opinion of the app.
  • Secure Communication: By following the recommendations of MSTG on secure communication practices, sensitive data transmitted between an app and servers will be protected. Knowing that data is being transmitted securely gives users greater trust.
  • Transparent Permissions & Authorizations: The guide emphasizes the proper implementation of authentication & authorization mechanisms. Users will be more satisfied When they feel in control of the app and their interactions.
  • User Confidence: A mobile application that adheres to security best practices will instill confidence in its users. Users are more likely to engage with an app if they feel it takes security very seriously. This confidence leads to a positive experience for the user.
  • Minimal Downtime Due to Security Incidents: Security incidents are less likely to cause downtime if secure applications adhere to MSTG guidelines. Users value applications that are always available and functional.
  • Adherence to Platform Guidelines: MSTG addresses security concerns specific to Android and iOS. By following these guidelines, developers can ensure their apps are aligned with platform standards and create a more seamless, familiar user experience.
  • Avoiding Security-Related User Frustration: Security-related issues such as account compromises and data leaks can lead to frustration among users. Implementing the security measures recommended by MSTG can help mitigate these issues and contribute to a positive user experience.

Related Content

Receive Zimperium proprietary research notes and vulnerability bulletins in your inbox

Get started with Zimperium today