Mobile App Security Testing Explained: Tools, Techniques, and Real-World Insights

#mobileapp #securitytesting

Think of your smartphone as a vault, keeping your secrets, finances, and your digital life, all within the confines of the app. A simple vulnerability within the app can allow hackers to dance right into your life. Mobile apps are being attacked with threats that are as frequent as the taps, taps, swipes, and updates, making the security of mobile apps a game of high stakes that you cannot lose. The difficulty is that threats develop at an average speed much faster than you can say “app update,” not to mention the complexity of a mobile ecosystem that rarely makes security easy. Speed to deploy features often times means that security can take a backseat, and users want the app to work without concerns of privacy or security.

In this blog, we’ll take a practical look at why mobile application security testing matters more than ever, walking you through every phase, from identifying attack vectors like insecure storage, communication flaws, and code tampering. We will address the types of the most common attacks, who should be testing, and the critical steps to making security a critical pillar of trust and adoption in your app. There is no question, if you are building, testing or managing mobile apps, you have a role in understanding these threats and testing for them. Hopefully you will be able to recognize, and test for, problems specific to mobile, be aware of platform specific issues like rooting or jail breaking, understand how to turn on hardware-backed security, and are aware of best practice in reporting and remediation.

Once you finish this guide, you will be in a much better position to protect users data, understand and follow industry best practices, and have security checkpoints at every step in your development life cycle turning mobile security from an afterthought into a feature. Let’s get started!

Introduction to Mobile App Security

Smartphones are not just a tool for communication in this hyperconnected world: they are personal safes, business workstations and entry points to sensitive data. This centrality has led smartphones to the center of a global security breach. Attackers no longer settle on desktop attacks, they run sophisticated espionage campaigns and even sophisticated malware directed fully against mobile apps. Mobile attacks take advantage of mobile app unique vulnerabilities like poorly protected API’s or improperly configured cloud integrations, which are often undetected until a breach occurs.

The financial and reputational damage associated with breaches is highly inaccurate. Data shows that the average cost of a data breach is now $4.8 million, and mobile incidents are a big part of that increase. In an investigation, the scope of damage does not include the loss of data, decreased productivity, and the loss of user trust in the app. Often, it can take years for a company to repair damage to brand reputation and trust with customers.

If the threat landscape isn’t daunting enough, it is evolving at a rapid pace, and with great complexity. Attackers can be very agile, taking advantage of not just malware, but more obscure ways of attacking such as multi-factor authentication (MFA) fatigue or social engineering. Users are often the weakest chain in the mobile security chain despite being the target audience. Users fall victim to phishing, access unsafe networks, or some never consider upgrading their software.

On one hand, developers have to release features faster, which may not allow for thorough security measures. Conversely, developers contend with more hidden, structural attack surfaces from APIs and cloud services that may be out of view for those securing and monitoring access and system and application interfaces. In either event, security should be engraved, rather than bolted on. Security should be part of all mobile app development efforts, from inception through implementation. Security will become a primary component related to user acceptance and adoption. Security should also exceed beyond protection of sensitive data. It should also allow organizations to effectively address regulatory requirements and build user trust in their mobile entity.

Why Mobile Application Security Testing Matters ?

Mobile application security testing is no longer a “nice to have,” it is a critical requirement if an organization wants to protect their users, their reputation, and their business continuity. Most apps handle personal and financial data, and many apps handle sensitive data. There is a lot at stake.

We have listed some strong reasons for why security testing every mobile app is truly essential:

Securing User Data & Privacy Security testing protects sensitive user data – personal data, payment data or credentials – from unauthorized access and leaks. Finding vulnerabilities early allows organizations to limit leaks of sensitive data which could harm users and destroy trust in an organization.
No Damage to Reputation & Money Lost An incident can be extremely costly. Companies can incur financial losses in the millions, legal liabilities or even damage their brand for a long time. Proper security testing can only mitigate the risk of such breaches, and create confidence in your customer base.
Compliance with Regulations & App Store Guidelines Regulating data under frameworks like GDPR, HIPAA or PCI DSS, or undergoing enforcement measures within app stores like Apple or Google Play, by having security testing you can limit the risk of hefty fines, app removal, app rejection and generally ensure your app is in good standing.
Lowering Future Maintenance Costs Finding and remediating vulnerabilities early in the build of your software is much cheaper if they are identified before release, just like finding and fixing a leak in a boat before it sinks. Finding exploitable vulnerabilities in your software as early as possible is beneficial because it extends the vulnerability fix solution lifespan, eliminates the need for costly expensive emergency fixes, and lowers technical debt. Even if it seems costly now, investing in testing will lead to significant gains in avoiding maintenance costs down the road.
Making Secure Releasing an Easy Ride Within DevOps Pipelines By embedding security testing into your CI/CD pipelines, you are evaluating weaknesses each time you have a release. The more times you can evaluate a security error the faster, easier and consistently you can safely deploy. This is immensely critical for helping you keep up with the pace of developing modern applications today.
Creating User Trust and Brand Loyalty Users will ditch an app that they don’t trust, and one security incident can deeply harm your reputation. Regularly assessing your software for security issues signals to your users that you are valuing their safety and security as a user, which additionally creates loyalty and puts your app in place as a reliable candidate with positive engagement and overall brand integrity in a noisy market. Users generally engaging with and sharing apps that they deem safe and reliable.
Discovering a Risk Early by Continuous Testing Waiting until you’ve been attacked to uncover exploitable vulnerability is a bet you cannot afford! Continuously testing security throughout the app lifecycle will enable your organization to discover vulnerabilities you would otherwise not be able to, and then be exposed by an attacker. This approach helps safeguard your users, and more importantly, consistently testing throughout the development phase can actually speed up your progress. By uncovering vulnerabilities earlier, it cuts down on the time needed for rework.

Okay, absolutely. Making sure your mobile apps are secure is the very first thing you need to do to protect user information, meet all the necessary rules and regulations, and make sure your app actually succeeds. By building security measures right into how you create and release your app, you’re not just protecting your business, you’re also building trust and creating strong connections with the people who use it.

Common Mobile Attack Types

Mobile applications pose a sometimes appetizing target for cybercriminals, as they often contain sensitive information (from personal information to financial credentials). Attackers exploit vulnerabilities found only in mobile environments which include a host of inter-related factors including mobility and connectivity, and a growing number of software ecosystems in play. Developers and security teams must know about common attack types to build applications which will keep users’ information safe from threats like those that can lead to data breaches, financial impacts, and loss of trust for existing users.

This article identifies and explains the most common mobile attack types, how they operate, and gives examples of real-world mobile attacks.

Insecure Data Storage

How It Works
Insecure data storage occurs when sensitive data, such as user id/password, payment data, or PII remains available on a mobile device, with no adequate encryption or protection. Insecure data storage is an attack vector for attackers when they have access to the device physically, using malware or accessing 3rd-party apps that are vulnerable. An attacker gains access to unprotected data without encryption or protection, such as databases, plaintext files, or sandbox areas of an app. A serious concern of insecure data storage is when devices are shared or stolen, as these attackers have minimal obstacles to retrieve data from insecure data storage.

Real-World Example
Back in 2018, a widely-used fitness app was found to be storing GPS coordinates and workout data in unencrypted files on Android phones. If someone had access to a rooted device, they could have easily grabbed this unprotected information, allowing them to track both the user’s location and their exercise routines. The incident sparked concerns about user privacy that led the app to strongly encrypt local storage data thereafter. Read more

Insecure Communication

How It Works
Insecure communication happens when an application transmits sensitive data (login credentials or financial information) over unencrypted or weakly encrypted channels. An attacker can capture this data by performing a man-in-the-middle (MITM) on an unsecured channel, one of the most common sources of weak security because of easy to attack unsecured Wi-Fi networks. Attackers took advantage of the absence or outdated TLS/ SSL protocols to capture user data that’s vulnerable to eavesdropping.

Real-World Example 1. Back in 2017, a few big banks like HSBC and Santander ran into trouble with the way they configured the security on their mobile apps. These SSL/TLS mistakes created a vulnerability known as a MITM attack. Essentially, this meant that anyone on the same public Wi-Fi network could have potentially stolen login information. This compromised thousands of accounts, prompting urgent updates to enforce proper encryption.

Reverse Engineering and Code Tampering

How It Works
Reverse engineering is basically taking an app’s code apart, like unzipping it, to figure out exactly how it functions. Code tampering, on the other hand, involves actually modifying the app itself, usually with the goal of getting around security measures, unlocking premium features for free, or even sneaking in malicious software. Decompilation tools such as decompilers are known for weaknesses in code obfuscation, exploiting the functionality of Android and its open ecosystem that doesn’t have any too restrictive. Both of these techniques have devastating revenue impacts for app developers in addition to opening the door for data theft, unauthorized access, or distributing malicious versions of an app.

Real-World Example
In 2016, Pokémon GO, a sensitive location-based mobile game, was reverse engineered and enabled hackers to modify or tamper versions of the app that defeated local location-based play restrictions and enabled free in-app purchases. These modified applications were served on third-party app stores that generated new revenue loss for the game and exposed unsuspecting user devices to malware. Developers of the game responded to the level of code without escalation to 9 days of improved code obfuscation strategies and integrity checks going forward. Read More

Insecure Authentication

How It Works
Insecure authentication manifests when an application fails to sufficiently validate user identities from various weaknesses such as weak session management, predictable session tokens, or insecure biometrics. Attackers exploit insecure authentication to bypass the login altogether and take advantage of a compromised user account, or access sensitive features of the application. This is more serious if the application exposes the user to financial or personal data.

Real-World Example
In 2019, a popular ride-sharing application had insecure session token management in that it could predictively expose session IDs. An attacker was able to hijack user accounts and start unauthorized rides (along with other account abuse). As a result, the company completely overhauled its authentication system by implementing strong token randomization and defining short session expires. Read More

Side-Channel Attacks

How It Works
Side-channel attacks exploit unintended information leakages due to the physical, or operational, characteristics of devices, such as power consumption, touch-screen occurrences, or sensor data (gyroscope, accelerometer, etc.). Attackers are able to exploit these sources of information leakage to infer sensitive information (passwords, cryptographic keys, etc.) without even looking at the app code. Mobile devices are particularly prone to side-channel attacks provided they are full of sensors and many opportunities to leak information via sensor data.

Real-World Example
In a 2017 paper, an attacker used accelerometer data as a side-channel attack against a mobile payment app, reconstructing the known PIN values using location data from the touchscreen of the mobile device. The attack itself used subtle movements of the device to reconstruct user input. There are significant implications for the research, and apps must be do a better job assessing whether information from sensors is being used or not and if there is any protections against these unconventional types of attacks. Read More

Who Conducts Mobile Application Security Testing?

Mobile application security is a battlefield, and the armies that therefore defend your app are diverse. Within the ranks of these armies, the personnel are a variety of skills that can outwit the clever sleuths or cybercriminals they are battling. From house guards (those working for the App) to world hacker collectives, these positions are the leading roles in a strong defense against the threats that could destroy your App. Here is each of the critical players in battle to make sure that your mobile app can withstand any attempt to attack. Each will have their own operating advantage (which is unconventional) to help fend off cybercriminals.