What is Application Hardening?

Explore application hardening’s importance, best practices, and techniques in this guide. Learn how app hardening plays a vital role in software security.

Understanding the Process of Application Hardening

Roles in the Application Hardening Process

In the process of application hardening, the roles of the Application Security Engineer, the Application Architect, and the DevSecOps Manager are pivotal, each contributing unique skills and perspectives to enhance the security of the application lifecycle.

The Application Security Engineer focuses on implementing and testing security measures. They are directly involved in coding secure software, identifying vulnerabilities, and applying hardening techniques like code obfuscation and integrity checks. Their expertise ensures that security considerations are embedded in the application.

The Application Architect designs the overall structure of the application, ensuring that it not only meets functional requirements but also incorporates security as a core component. They work closely with the security engineer to align the application’s architecture with best security practices, making it resilient against potential threats.

Meanwhile, the DevSecOps Manager bridges the gap between development, security, and operations. They oversee the integration of security at every phase of the software development lifecycle, promoting a culture of continuous security improvements. This role is crucial for ensuring that hardening strategies are consistently applied across all development stages.

Overview of the Application Hardening Process


Code obfuscation is a fundamental technique in the application hardening process, designed to protect the application by making the code more difficult for unauthorized individuals to understand and manipulate. This process involves transforming readable code into a complicated, less intelligible format that retains its original functionality. By doing so, code obfuscation helps to shield sensitive logic and data from attackers, significantly reducing the risk of reverse engineering and intellectual property theft. Through various algorithms and transformations, such as renaming variables, scrambling code execution sequences, and inserting dummy code, obfuscation ensures that the application remains secure and resilient against unauthorized scrutiny and modifications.

Anti tamper

Anti-tamper techniques are a critical component of application hardening, designed to protect applications against unauthorized modifications and ensure their integrity. These techniques detect and respond to attempts at tampering, such as changes made to the code or data after the application has been released. By embedding checks within the application, anti-tamper mechanisms can verify if the application is running in an altered state or unauthorized environment and take predefined actions to mitigate potential threats. These actions could include shutting down the application, alerting security personnel, or reverting to a known-safe state. This layer of security is vital for applications operating in high-risk or uncontrolled environments, as it helps maintain the trustworthiness and functionality of the software, safeguarding both the users and the creators from the consequences of malicious alterations.

Ensuring Code Integrity

Ensuring code integrity is a vital part of application hardening, focusing on maintaining the authenticity and correctness of an application’s code throughout its lifecycle. This process involves techniques to verify that the code has not been altered or corrupted from its original, verified state. Cryptographic hash functions, digital signatures, and checksums are commonly used to create unique digital fingerprints of the code. These identifiers are then validated against trusted sources or baselines to detect any unauthorized changes. This practice is crucial for preventing the execution of tampered or maliciously altered code, particularly when applications are designed to be downloaded and consumed on the open internet or “in the wild”. By safeguarding the integrity of the code, enterprises can protect the security of their applications and the data they handle, thus maintaining user trust and regulatory compliance.

Application Monitoring

Monitoring attacks on applications is an essential security measure that involves continuously observing application behavior to identify and respond to potential security threats. This proactive approach depends on building the ability for the app to monitor itself into the application during the development cycle so that it can detect unusual activities that may indicate an attack, such as unauthorized access attempts, or anomalous behaviors. Effective monitoring allows security teams to quickly isolate and mitigate threats, minimizing potential damage. Additionally, the insights gained from monitoring can be used to refine security measures and hardening techniques, adapting to new threats as they emerge. Building monitoring capabilities into apps is crucial in maintaining the security and resilience of applications, especially when those apps are designed to be used in the open internet or “in the wild”.

Runtime Application Self Protection

Runtime Application Self-Protection (RASP) is a security technology that provides real-time threat response within an application’s runtime environment. RASP integrates security directly into the application, enabling it to mitigate attacks as they occur. This method is designed to identify and counter threats by analyzing the application’s behavior and context, such as the data it processes, the control flow, and the use of system resources. When a potentially malicious interaction or environment is detected, RASP can take immediate action, such as terminating a session or even modifying the application’s execution to prevent exploitation. By protecting applications from the inside, RASP enhances security requiring external action from a Security Operations administrator, making it a valuable tool for securing modern applications in dynamic environments.

Best Practices for Application Hardening

Best practices for application hardening involve a multi-layered security approach that includes code obfuscation to protect against reverse engineering, implementing anti-tamper mechanisms to guard against unauthorized modifications, and ensuring code integrity through cryptographic verification techniques. Additionally, adopting Runtime Application Self-Protection (RASP) enhances security by detecting and mitigating threats in real time within the application’s operational environment. Regular monitoring of application behavior is also crucial to detect and respond to attacks swiftly. By integrating these practices, organizations can fortify their applications against a broad spectrum of security threats, ensuring robust protection throughout the application’s lifecycle even when they are used by consumers on the open internet “in the wild”.

Testing applications that have been fortified against dynamic analysis presents significant challenges because these security measures actively obstruct the tools and techniques typically used for diagnostic and testing purposes. Dynamic analysis tools, like debuggers or runtime instrumentation, rely on the ability to inspect, modify, or monitor the application’s execution state as it runs. However, when applications are hardened with techniques designed to resist dynamic analysis, these tools can be detected and blocked, or the application might alter its behavior in their presence, thereby skewing test results. This intentional obstruction not only complicates performance and functional testing but also makes it difficult – if not impossible — for developers and testers to perform thorough security assessments and quality assurance, as the usual introspective capabilities they rely on are effectively neutralized.

Penetration Testing

Penetration testing hardened applications requires a nuanced approach, as these applications are specifically designed to resist automated scanning and common exploitation techniques. While automated penetration testing tools provide a useful initial scan, identifying surface-level vulnerabilities and common security issues, they often fall short when faced with the sophisticated defenses of hardened apps. Effective penetration testing of such applications necessitates advanced manual testing by skilled human testers. These experts can think creatively and adaptively, simulating the actions of real-world attackers who may employ complex strategies beyond the scope of automated tools. Human testers can explore deeper into the application’s logic, uncovering hidden vulnerabilities that automated tools might miss due to the obfuscation and anti-tampering measures in place. This manual, in-depth exploration is critical for thoroughly assessing the resilience of hardened applications, making it an indispensable component of a comprehensive security strategy.

Application Hardening Compliance Standards

Application hardening is closely tied to several compliance standards, each designed to ensure that software applications meet specific security benchmarks to protect sensitive information and prevent breaches. Here are some key compliance standards related to application hardening:

PCI DSS (Payment Card Industry Data Security Standard)

This standard mandates that any software handling credit card transactions must be securely developed and maintained. It includes requirements for encrypting transmissions, maintaining secure systems, and implementing robust access control measures.

HIPAA (Health Insurance Portability and Accountability Act)

For applications dealing with protected health information (PHI), HIPAA requires ensuring the confidentiality, integrity, and availability of PHI. This involves implementing security measures that protect against unauthorized access to or tampering with patient data.

GDPR (General Data Protection Regulation)

Although not specifically focused on application hardening, GDPR mandates the security of processing personal data. This includes using appropriate technical measures to ensure data security, which can encompass various application hardening techniques.

ISO/IEC 27001

This international standard provides requirements for an information security management system (ISMS). It includes detailed specifications for acquiring, developing, and maintaining secure systems, which are often supported by application hardening practices.

NIST (National Institute of Standards and Technology) Special Publication 800-53

This publication provides a catalog of security and privacy controls for federal information systems and organizations, including recommendations for application hardening to protect information systems from attack.

OWASP (Open Worldwide Application Security Project)

While not a compliance standard, OWASP provides guidelines and best practices for secure application development, which are widely respected and followed throughout the industry. The OWASP MASVS, for instance, outlines critical security risks to mobile applications and suggests hardening techniques to mitigate these risks.

Compliance with these standards often requires a combination of encryption, access controls, regular security assessments, and other hardening techniques to mitigate vulnerabilities and protect against potential attacks. Organizations must carefully implement these practices not only to comply with legal and regulatory frameworks but also to safeguard customer trust and corporate integrity.

The Future of Application Hardening

Emerging Trends

Emerging trends in application hardening reflect the evolving landscape of cybersecurity threats and the increasing sophistication of attack vectors. Here are some of the key trends shaping the future of application hardening:

Shift Left Security

Organizations are integrating security earlier in the software development lifecycle, a practice known as “shifting left.” This involves incorporating security measures like threat modeling, secure coding practices, and static code analysis during the design and development phases, rather than as a final step before deployment.


Building on the concept of shifting left, DevSecOps integrates security practices within both the development and operations phases of software development. This approach ensures continuous integration and delivery pipelines are fortified with security checks, automated testing, and real-time vulnerability assessments, making hardening a continual process.

Use of Artificial Intelligence and Machine Learning

AI and ML are being leveraged to enhance application hardening techniques. These technologies can predict and identify potential vulnerabilities by analyzing code patterns and past incidents, enabling proactive rather than reactive security measures.

Enhanced Code Obfuscation Techniques

As attackers become more adept at de-obfuscating code, new and more sophisticated obfuscation techniques are being developed. These include polymorphic and metamorphic code, which change each time they are deployed, making it exceedingly difficult for attackers to analyze or predict the code’s functionality.

Zero Trust Architecture

Embracing the zero trust model, which assumes that threats could be internal or external, organizations are implementing more rigorous access controls and continuously validating security, even within their own networks. This model drives demand for application hardening beyond apps that operate outside the firewall to apps that operate inside the firewall.

These trends signify a broadening scope of application hardening, emphasizing not only protection against external threats but also ensuring robust internal controls and integrating security into every aspect of application development and deployment.