This table breaks down each risk, making it clear why these vulnerabilities matter and how to prevent them.

What’s the Number One Risk for Mobile Devices According to OWASP?

Let’s get straight to it—OWASP lists Improper Platform Usage as the top security risk for mobile devices. Sounds technical, but basically it means developers abuse built-in security features or don’t use them at all.

This is a big problem because many apps are developed fast to keep up with demand, especially in fintech and mobile banking. The faster the development cycle, the easier it is to miss security essentials—sometimes with serious consequences.

Digging Deeper into the Biggest Risk: Improper Platform Usage

This risk covers several common mistakes when working with mobile operating systems:

• Storing sensitive data improperly instead of using secure storage solutions.
  
  
• Not using strong auth methods, like multi-factor auth (MFA)
  
  
• Using outdated or insecure APIs that introduce security flaws.

At first glance, these seem like small things, but they can lead to big security holes—holes that hackers love to exploit.

Why is Improper Platform Usage So Prevalent?

There are a few reasons why this keeps happening:

• Developers prioritize functionality over security. Not every developer is a security expert, and when the app needs to work well, security gets left behind.
  
  
• Tight schedules and budgets force shortcuts. Rushed development cycles mean security gets an afterthought.
  
  
• Mobile platforms are constantly evolving. Keeping up with iOS and Android security changes is hard, especially when supporting older devices.
  
  
• Third-party tools are relied upon. Many apps use external SDKs or libraries, which can introduce vulnerabilities if not vetted carefully.

Real-World Examples of Exploits and Impact

To see why this is a big deal, let’s look at a fictional example:

A popular banking app stores user session tokens in plain text in local storage. If someone gains temporary access to a user’s phone, they can steal that token and take over the account—no password needed.

Or a fintech app that doesn’t do certificate pinning for secure communication. A hacker can launch a Man-in-the-Middle (MitM) attack, intercepting login credentials and financial transactions.While these are fictional examples, real breaches like this happen all the time. Once trust is broken, users leave and a company’s reputation takes a big hit.

Mitigation Strategies and Best Practices

The good news? These risks can be reduced or avoided altogether by following best practices:

• Follow platform security guidelines. Apple and Google provide security recommendations for a reason—use them.
  
  
• Secure sensitive data. Store critical data like API keys, encryption keys and credentials in iOS Keychain or Android Keystore, not standard storage.
  
  
• Use certificate pinning. Prevent attackers from intercepting app communication.
  
  
• Strengthen auth. Implement MFA and don’t hardcode credentials.
  
  
• Test for security regularly. Use tools like MobSF and OWASP ZAP to find vulnerabilities early. Keep everything up to date. Outdated dependencies come with known security flaws—patch them.
  
  

So, Improper Platform Usage is the top mobile security risk—but it’s not unavoidable. By being proactive and building security into your development process from day one, you can protect your app, your users and your business.

M2: Insecure Data Storage

Source: Freepik

Why is insecure data storage a big deal? In essence, storing sensitive data in plain text is a free invitation for attackers. If user credentials, API keys, and financial information aren’t protected on a device, anyone with access can get them. A simple hack is all it takes. With just physical access or a piece of malware, your users’ data can be compromised.

Imagine a mobile banking app that saves passwords in plain text. A stolen phone, a curious thief, and suddenly, someone else is draining accounts—no hacking skills needed, just a little snooping. That’s the danger of insecure data storage.

How to prevent it: Always encrypt sensitive data. Use secure storage solutions like iOS Keychain or Android Keystore. And never, ever store passwords or API keys in plain text. A little security now saves a world of trouble later.

M3: Insecure Communication

If a fintech app sends payment details over HTTP instead of HTTPS, an attacker on the same Wi-Fi can capture that data. Just like that, sensitive financial transactions are exposed to prying eyes. And it’s not just fintech—any app that transmits data without encryption is putting user information at risk.This kind of attack is known as a Man-in-the-Middle (MitM) attack. The hacker positions themselves between the app and the server, silently intercepting everything being sent. Login credentials, credit card numbers, personal messages—it’s all up for grabs.

How to prevent it: Always use HTTPS with TLS (Transport Layer Security). Consider certificate pinning to block attackers from using fake certificates. Securing data in transit isn’t optional—it’s the difference between protecting your users and handing their information to an attacker on a silver platter.

M4: Insecure Authentication

Weak authentication is like leaving your front door unlocked and hoping no one notices. If your app doesn’t properly verify users, anyone can slip in—no lockpicking required.

Take an e-commerce app that only checks for a username but skips the password. That means if someone knows a valid username (which isn’t hard to guess), they can log in instantly. No password. No challenge. Just wide-open access to someone else’s account.

Even worse? Hardcoded credentials—baking in login details directly into your app’s code. If an attacker decompiles the app, they can find these secrets and use them to wreak havoc.

How to fix it: Use strong authentication methods. Require proper passwords (and enforce good password rules). Implement multi-factor authentication. And never, ever hardcode credentials into your app. Because once they’re out in the wild, you can’t take them back.

M5: Insufficient Cryptography

This happens when an app uses weak or improper encryption. This can be due to using outdated algorithms or improperly implemented cryptographic protocols.

Real World Example: An app that uses MD5 to hash passwords. MD5 is broken and can be cracked easily with modern computing power.

Prevention Tips: Use strong cryptographic algorithms like AES-256 and follow best practices for key management.

M6: Insecure Authorization

Source: Freepik

Not all users should have the same level of access—but if your app doesn’t enforce strict authorization rules, that’s exactly what can happen. A regular user could suddenly have admin privileges. Someone with no business seeing private data could waltz right in.Imagine a social media app where role verification is handled poorly. A regular user stumbles upon an admin panel—no hacks, no exploits, just bad access control. Suddenly, they can edit posts, delete accounts, or view private user data. That’s a disaster waiting to happen.

How to prevent it: Lock down permissions. Always check user roles on the server side (client-side checks alone won’t cut it). Make sure every action a user takes is properly authorized—because once access is granted, it’s tough to take back.

M7: Client Code Quality

Sloppy code isn’t just a developer’s headache—it’s an open door for attackers. Bugs and poor coding practices can introduce serious security risks, from SQL injection to buffer overflows. One small mistake, like failing to validate user input, can be all it takes for an attacker to slip in and wreak havoc.

Picture this: A messaging app lets users send status updates but doesn’t check what kind of input it allows. An attacker sneaks in a carefully crafted malicious script instead of regular text. Suddenly, they can manipulate the app’s behavior, steal user data, or even take control of certain functions. All because no one sanitized the input.

How to prevent it: Write secure code from the start. Sanitize every bit of user input. Run regular code reviews. Security isn’t something you patch in later—it needs to be baked into development from day one.

M8: Code Tampering

This is the risk of app modification or tampering. Attackers can decompile your app, modify its code and then redistribute a malicious version. it can happen,forinstance, with a popular game app. The software gets hacked and the modified version includes malware that steals user data.

Prevention Tips: Use code obfuscation, integrity checks and code signing to make it harder for attackers to tamper with your app.

M9: Reverse Engineering

Think of your app’s code like a locked diary. Reverse engineering is when attackers crack it open, reading everything inside—encryption keys, proprietary algorithms, and sensitive logic. Once they get access, they can copy your app’s features, exploit vulnerabilities, or even create malicious clones.It happens more often than you’d think. Imagine a competitor decompiles your app, steals your unique functionality, and releases a near-identical product. Worse, an attacker could analyze your code to find weak spots, then craft an exploit to compromise your users.

How to prevent it: Make their job harder. Obfuscate your code, encrypt sensitive parts, and strip out anything that doesn’t absolutely need to be there. Security through obscurity isn’t a perfect defense, but every extra hurdle helps.

M10: Extraneous Functionality

Developers leave behind traces—debug features, test modes, or hidden admin tools meant for internal use. The problem? If these aren’t removed before launch, attackers can find and exploit them.

Picture this: A mobile banking app accidentally ships with a forgotten debug mode still enabled. A savvy attacker discovers it, bypasses authentication, and gains unrestricted access. That one overlooked feature just became a massive security hole.

How to prevent it: Before release, audit your app for any leftover test code or hidden backdoors. Regular security assessments help catch what you might have missed—because attackers will definitely be looking.

Impact on Mobile Applications and User Data

You should care about the OWASP Mobile Top 10 because it helps protect user data from breaches and theft, maintains trust in your brand, and keeps you compliant with regulations like GDPR and CCPA. On top of that, security can be a competitive advantage—users are more likely to trust an app that takes their privacy seriously. These aren’t just technical concerns; they’re business risks that can directly affect your bottom line. The more proactive you are, the better prepared you’ll be to prevent costly security failures.

Prevention Tips