Demystifying Mobile Application Hardening: Techniques and Best Practices

What is Mobile Application Hardening?

Mobile application hardening refers to the process of securing mobile applications against various threats and attacks. It involves implementing a range of security controls and techniques to protect the application code, data, and functionality from unauthorized access and manipulation.

One key aspect of mobile application hardening is code obfuscation, which makes the code difficult for hackers to understand and reverse engineer. This is achieved through techniques such as control flow obfuscation, string encryption, and asset encryption. White box encryption is also employed to protect sensitive data by encrypting it at the code level. When code obfuscation is not practical because the data to protect must be (partially) displayed, linked to other accounts or other data, or sent to a remote network, data obfuscation can be a solution. 

Runtime application self-protection (RASP) is another important component of mobile application hardening. It enables applications to defend themselves at runtime against dynamic attacks by continuously monitoring and analyzing their own behavior. By doing so, RASP can detect and respond to security threats in real-time, reducing the risk of successful attacks.

Additionally, mobile application hardening encompasses other security measures such as device authorization, secure storage, data protection, secure connectivity, anti-tampering mechanisms, and anti-cloning techniques. These measures help enhance the overall security posture of the application and mitigate potential risks.

Why is application hardening important? 

According to the Business of Apps App Data Report 2023, 142.6 billion mobile apps and games were downloaded in 2022, of which 110 billion were Google Play apps and 32.6 billion apps were on iOS. An increase to a total of 200 billion apps by 2025 is expected. Meanwhile, Veracode's 2023 Report on the State of Application Security states that over 74% of apps had at least one security flaw found in the last scan over the last 12 months, including over 69% with at least one OWASP Top 10 flaw, and 19.2% of the flaws were labelled as "high severity". 

Mobile application hardening helps to identify and address potential security vulnerabilities within the application code, as well as provide additional layers of protection against external attacks such as malicious code injection or reverse engineering. This is especially important due to the sheer volumes of applications being released and used every day, and the risk of exploits which could be significantly damaging to businesses. Such damage could result from data leakage, identity theft, denial of service attacks, financial frauds, intellectual property theft, reputational damage, and more.

What are the best practices for Mobile Application Hardening?

Best practices for mobile application hardening include:

1. Implement security controls during development to minimize risk. Both ENISA and OWASP provide guidance on such controls.
2. Leverage application security assessment tools to identify potential vulnerabilities and threats which may be present in the mobile app codebase. 
3. Layer application security, for example by using a combination of code hardening techniques and protections at runtime. 
4. For RASP, use the sentinel approach that involves incorporating monitoring and analytics tools in the application, which can be used to detect malicious activity and proactively take defensive action against it. 

It is also important to ensure that applications are regularly updated. As new vulnerabilities and threats are discovered, developers must continuously improve security controls in order to strengthen their app's security posture. 

Finally, developers should also ensure that their applications are compliant with industry regulations and standards. This includes ensuring that applications abide by the data privacy and security requirements of relevant governing bodies and adhere to industry-specific compliance regulations.