App Security Audit – Top Reasons Why You Need One And Best Practices

Аpp security isn’t a feature – it’s a necessity. A single breach into your software can cost you a lot in the short term, and mistrust from your userbase in the long term. 

Even with that in mind, the latest findings show that more than 50% of available apps fail the most basic security tests. Sometimes developers are too focused on pushing the latest update that will enhance their UI or developing the most intuitive user experience, while security takes a backseat, resulting in insanely costly data breaches. 

Today, our smartphones and computers foster a ton of sensitive data. A single hack and your user’s identity, payment info, address, and current location could be exposed for malicious actors to exploit as they please. 

This article aims to raise awareness of the importance of app security audits and some of the best practices businesses should adopt at all times. 

Why you need an app security audit

As we briefly mentioned, any security breach can potentially destroy your company’s budget and reputation. And sadly, as the amount of sensitive data becomes ever more present in our lives, the number of hackers targeting small and medium businesses is increasing by the day. 

Here are some bone-chilling numbers for you: 

  • $400 billion is the estimated annual business loss to cybercrime globally. 
  • 94% of organizations experienced phishing attacks. 
  • 73% of organizations impacted by impersonation attacks have experienced a direct loss. 

Common attack sources on apps

Below is the list of the most common attack types that hackers might attempt against your app. 

Browser attacks

These attacks include methods such as phishing, clickjacking, data-caching, and man-in-the-middle attacks. All the attack methods that happen using a web server or a browser can be used to exploit a web-based mobile or desktop application.

Hackers use malicious scripts and inject them into the app components that are served using the browsers. 

Injections at the local application level that mainly target data stores may result in conditions such as access of paid content locked for trial users or file inclusions, which may lead to abusing functionalities such as SMS, and so on.

SMS attacks

Attackers can potentially gain access to your phone with a simple SMS message. While this might seem like a problem for the phone manufacturer or operator, in reality, mobile apps can leave open doors for SMS hacks. 

Recently, this kind of vulnerability was exploited through twitter’s mobile app to hack its CEO’s account. 

More importantly, hackers can use SMS-based attacks to execute more adverse hacks such as an account takeover (ATO)

App-logic attacks

Through app-logic attacks, hackers exploit vulnerabilities in the app logic to gain access to sensitive information like email addresses and passwords. 

They exploit common vulnerabilities such as improper SSL Injection, weak encryption, or improper permission structure. 

Avoiding attacks – best practices

When developing an app, there are several best practices that can keep you on the safe side from malicious attacks. While you can’t always avoid hackers, it’s good practice to make it not worthy for them to even attempt an attack on your software. 

Clean and secure code

The starting point for any hacker will be the bugs and vulnerabilities left in your code. If you leave space for hackers to exploit, they will. Ensuring the shipped app is clean of any vulnerabilities is essential. 

Furthermore, unless you are running an open-source operation, secure the source code of your app as soon as possible. Usually, most of the source code resides on the client-side, including the UI and the business logic which presents a threat if this code was accessible to attackers.

Obfuscating your code to make it unclear to understand will make it difficult to reverse-engineer and breach its security measures. Also, make it so that your code is easily updated or patched, in case a vulnerability is detected down the road. 

Encrypt all data

While securing the source code is a step in the right direction, you should equally encrypt and safeguard all the data that is exchanged over your app. 

You will eventually need to store data on the device for all sorts of reasons. This data can include critical information such as user credentials or payment info, which is why you should always make sure that the data you’re storing on the user’s end is encrypted to prevent its leakage.

Furthermore, use the best encryption tools that are available. Instead of cryptographic protocols like MD5 and SHA1, use more secure SHA-256 standards for key and password encryption. 

Use high-level authentication

The biggest and most high-profile security breaches happen because of a lack of security during authentication. 

The process refers to the passwords and other personal identifiers that act as barriers to entry. While a large portion of this security is user-dependent, you should encourage and allow only highly secure authentication methods, provide alternatives like 2-factor authentication and strong alphanumeric passwords. 

If your app is overly sensitive (e.g. finance, banking, cryptocurrencies) it might be a good idea to even add biometric authentication to increase safety.

Use least-privilege principle

This means that your app should request the privileges it needs and only those. Never should an app request require access for more privileges than it needs to function. If you don’t need access to your user’s contacts, don’t ask for it. 

With this, you limit the network connections and reduce the chances of data breaches and backdoor exploitation. 

Test frequently and repeatedly

App security audits are essential because securing an app is a neverending process. Test your app for vulnerabilities using emulators, invest in hacking contests, and fix any weakness with recurring and regular patches and updates. 

Repeat testing will allow you to uncover your app’s vulnerabilities and gradually close them off to provide a safer software for your users. 


A majority of users usually assume that the application they install is devoid of vulnerabilities. As such, they don’t give a second thought to the permissions they give to the app. However, if a breach happens, it will fall upon you as a business and a developer. 

With cybercrimes rising as time goes by, you should do regular app security audits and respect the few guidelines we enumerated in this post.