9 Biggest Mobile App Security Risks & How to Prevent Them

Mobile devices aren’t just small personal computers—they differ drastically in both hardware and software when compared with other devices. As a result, mobile security risks can differ quite drastically from the security risks of laptops or desktop computers. That’s why mobile app protection is important.

When we talk about mobile devices, generally we mean smartphones: devices that can connect to the internet and install software in the form of applications. Almost 80% of the world owns a smartphone, and app downloads are only going up every year (230 billion downloads in 2021!). If your company has an app, you need to understand the unique security vulnerabilities of smartphones and mobile apps.

Mobile App Security Issues at a Glance:

Poor API Protection
Weak Server-Side Controls
Client-Side Injections
Unsafe Sensitive Data Storage
Hardcoded Password or Keys
Bad Source Code Security
Sensitive Data Leakage
Unsafe Data Transmission
Inadequate Logging and Monitoring

How is the security of mobile apps different from website protection?

Securing a mobile application is totally different from securing a website, a web app, or even a software application for laptops or desktop computers. After all, mobile developers have to work within the constraints of both a smartphone’s operating system (iOS or Android) and the app store that they want to publish the app on (called the App Store for iOS and Google Play for Android).

That’s why many developers focus exclusively on mobile apps. They’re mobile developers; they don’t program in HTML, CSS, or vanilla JavaScript. Instead, they program in Java or Kotlin for Android, Swift for iOS, or React Native if they want to code in one programming language for both operating systems. The development process for an app is drastically different when compared with that of a website or web app.

The development process is also where most mobile app security issues begin. Even a small oversight in a developer’s code can lead to a hacker, fraudster, or cybercriminal entering your app to steal data or take over a user’s account.

9 Mobile App Security Risks in 2023

It’s all too easy to cut corners on mobile app security. Companies want to release apps quickly and development teams are often understaffed and overcommitted. Security becomes an afterthought, even though it shouldn’t be. If you want to protect your company’s reputation and revenue, you have to pay close attention to the following 9 mobile app security risks.

Poor API Protection

If you’re building an app, you’re almost certainly going to use at least one API. A mobile app API allows an application to take data from another application. For example, it’s what allows a travel booking website to take information from a wide variety of hotels and airlines to put it all together in a neatly organized way. As another example, it’s what allows Google Maps to display directions to a location. Most modern apps rely on APIs for much of their functionality.

Many developers forget to protect their APIs. They assume that bad actors won’t find them interesting, but the opposite is true. APIs provide access to stable, structured information—which is exactly what bad actors want. They will reverse-engineer your app to find out what APIs your app uses, run your app with an emulator, or use a mobile farm to find access points.

How to Prevent Poor API Protection

As with many of the threats on this list, the biggest exploitation dangers come from malicious bots. Generally, bots have no reason to use your API, so when they do, it’s not a good sign. A bot protection solution specifically tailored for mobile apps will know how to detect bots and can block the bad ones while letting the good ones through.

Weak Server-Side Controls

Modern mobile apps have both a client and a server side. The client side is what the user sees. It’s the user interface, with all the flash and functionality. But to make it all work, the client side relies on the server side, which is responsible for making sure everything functions properly. Client and server usually communicate through an API.

Server-side vulnerabilities are common and easily exploitable through the often unsecured API. They can include code logic flaws, weak authentication rules, weak session management, insecure server configurations, access control vulnerabilities, and more. There are too many to list, but they will usually fall into two categories: code vulnerabilities or configuration vulnerabilities.

How to Prevent Weak Server-Side Controls

Because the client side of an app communicates with its server side through an API, you can block many threats by removing the ability of automated scripts to access your API. While this won’t stop manual threats and it also won’t fix server-side vulnerabilities, it will at least prevent your app from being very easily exploitable.

Client-Side Injections

One of the ways an attacker can try to break into your app is by sending it unusual data that leads to unauthorized access. That data is usually manipulated in such a way that your app will interpret it as executable code. For example, a mobile SQL database can be targeted by an attacker inserting a creative query where they receive private data from other users.

SQL injections are only one form of client-side injection. Another form is called Local File Inclusion, where the attacker uploads an executable file that your app reads and runs, which can lead to your app crashing or exposing sensitive data.

How to Prevent Client-Side Injections

One of the most effective ways to prevent client-side injections is through proper input validations, i.e. checking all incoming data (including from partners, regulators, and suppliers) to make sure it’s within reasonable boundaries of what’s expected. Proper input validation can mean:

Implementing a minimum and maximum value range check for data and length of a string
Adding a regex check that avoids “any character” wildcards like “.” or “*”
Asking for an exact match if input data options are fixed
Only allowing input data from an array of permitted values

Unsafe Sensitive Data Storage

Mobile apps, even banking apps, often store sensitive data locally. This means that your PIN number, credit card numbers, passwords, login details, and more are simply stored somewhere on your smartphone. What’s worse is that they’re often stored insecurely. If anyone tech-savvy gains access to your device (remotely or not), they can find and take all that data.

Sensitive local data is often stored insecurely because of improper encryption. Some mobile apps don’t encrypt local data altogether, which is the worst offense. Other mobile apps encrypt local data but don’t store the encryption keys properly, or they use custom encryption protocols that aren’t considered safe.

How to Prevent Unsafe Sensitive Data Storage

Data at rest has to be properly encrypted, with a strong encryption protocol that’s long been considered secure by the cybersecurity community. Don’t try to do anything fancy with a custom protocol. Chances are much higher you’ll make a mistake and accidentally expose sensitive local data instead of properly protecting it.

Hardcoded Passwords or Keys

This is the most basic of mistakes, but it still happens. Developers often hardcode passwords, API keys, or OAuth keys to make an application easier to implement, support, or debug. This means that these passwords or keys are written down explicitly somewhere in the code. When these hardcoded values are then discovered because an attacker reverse-engineered your app, you’re wide open for all kinds of exploitation.

How to Prevent Hardcoded Passwords or Keys

Developers hardcode passwords to make their lives a little easier, so provide them with a password management solution that securely stores their passwords or keys for them, so they don’t have to hardcode sensitive values. Additionally, frequently scan for hardcoded passwords—and if you catch one in a live app before anyone else does, immediately patch the issue away so no one can exploit it.

Bad Source Code Security

The source code of your application is what makes it work. It’s the building blocks. If you don’t secure your source code, you’re essentially giving away your competitive edge—your intellectual protocol—for free. Additionally, source code often coexists with API or encryption keys, authentication tokens, user passwords, and other sensitive data that you don’t want exploited.

When we talk about source code, we don’t just mean your source code. We mean all the source code you use, which can include code from third parties such as partners or suppliers or even simple open-source code. If any of it is insecure, your application is at risk.

How to Prevent Bad Source Code Security

You can prevent insecure source code with mobile app security testing tools that frequently or even continuously scan your source code for vulnerabilities. This can do most of the code review work, although you should still have manual code reviews to check for vulnerabilities. Additionally, you should store your source code securely and only give access to those who absolutely need it, and no one else.

Sensitive Data Leakage

Data leakage means exposing sensitive data online, either accidentally or on purpose. It’s what happened to the popular mobile parking app Parkmobile when a vulnerability in a third-party software led to a data leak that exposed the emails, dates of birth, license plate numbers, phone numbers, and more of 21 million users.

Sometimes, these leaks happen inadvertently. For example, Firebase is one of the most popular data-storage solutions for Android apps, but often improperly configured. Anyone who knows the right URL for an app built with Firebase can easily access the databases of that app, leaking sensitive user data.

How to Prevent Sensitive Data Leakage

One of the ways to prevent sensitive data leakage is to prevent data caching. Don’t store data in cache, because attackers can use that data to try and break into a user’s account. Users can clean the cache manually or developers can simply decide to not store sensitive data in cache. It’s perhaps a little more inconvenient for the users, but definitely makes for a more secure application.

Unsafe Data Transmission

We’ve previously said that unencrypted or poorly encrypted data at rest is unsafe, so it should come as no surprise that unencrypted or poorly encrypted data in transit is unsafe too. It’s not too complex for an attacker to intercept data as it travels across wifi (particularly insecure public wifis) or a mobile device’s carrier network.

While data in transit is often encrypted, it’s also often poorly configured, or the keys are handled improperly, or the developers use a customer encryption algorithm that’s not as secure as modern algorithms. Essentially the same problems as with unencrypted or poorly encrypted data at rest, except that hackers access it through different channels.

How to Prevent Unsafe Data Transmission

Use SSL or TLS protocols to transmit data. Even better, encrypt data before you send it through SSL or TLS, so that there’s a second security layer in case of a vulnerability in the SSL or TLS protocol. Additionally, protect data in transit against network interception attacks with proper certificate validation and authentication.

Inadequate Logging and Monitoring

Once your app is live, you want to know how it’s doing. You want to understand when problems show up, so you can respond in time without disrupting the user experience too much. But if you don’t have proper logging and monitoring systems set up, you won’t be able to do any of that. Instead, you’ll be left in the dark, with information gaps that won’t allow you to defend yourself against security incidents.

How to Prevent Inadequate Logging and Monitoring

The solution is to implement or create a system that will log and monitor all the important variables of your application. This includes launch time, UI response time, crashes, battery consumption, data consumption, but also unusual activity, failed login attempts, and other security threats.

Improving Security in Mobile Applications with DataDome

The most advanced threats are automated. Attackers have no time to manually scan every application for weaknesses, so they use bots. DataDome protects your mobile applications and APIs against these bots with its state-of-the-art bot blocker software. The software protects both server-side and client-side, through a small API module server-side and an extremely light, built-in SDK integration client-side.

Additionally, DataDome’s code is obfuscated, which means that attackers cannot reverse-engineer the software to understand how it works. The software also allows you to configure custom rules that you can apply to specific endpoints, and it monitors the type and quantity of incoming bot threats. If you want to see for yourself how it works, schedule a live product demo today.

Mobile App Security FAQs

What are mobile app vulnerabilities?

Mobile app vulnerabilities are weaknesses in your mobile app that attackers can use to exploit data, frustrate your users, or break your app. Mobile app security is often neglected and, as a result, many mobile apps are easy targets for hackers, criminals, and fraudsters. Mobile app vulnerabilities include hardcoded passwords, unsafe sensitive data in transit or at rest, client-side injections, and weak server-side controls.

What are the negative effects of mobile app vulnerabilities?

Most companies care deeply about the security of websites or web apps, but they don’t extend that care to their mobile applications. As a result, mobile apps often leak data or make it terribly easy for hackers, fraudsters, and cybercriminals to exploit data. This can lead to account takeovers and payment fraud for the user and lost revenue, reputational damage, and data privacy fines for the company.

How secure are mobile apps?

Many mobile apps aren’t very secure. Companies often put great care into securing their websites or web apps while neglecting their mobile apps. That’s why mobile apps are popular attack vectors for sophisticated hackers, fraudsters, and cybercriminals. However, if you make the effort to secure your mobile applications, you will stand out from the many who don’t.