12 Essential Best Practices for Building Secure Web Applications in 2025

Web application security is an important factor for businesses worldwide looking to promote their products and services online. No matter the industry, every web app is prone to  AI-based attacks, making them a significant threat to the unsuspecting apps. 

Even a well-known platform like Amazon sees up to 750 million cyberthreats in a day, with most determined to be made possible with the help of AI. This makes it imperative for all kinds of businesses to ensure their web application security is developed well before investing in online opportunities.

Establishing secure web application development is possible with the right cybersecurity procedures in place. In this article, you’ll discover some of the best practices you can implement whether you’re creating or enhancing your web app.

12 Web Application Security Best Practices

Effectively securing your web app requires addressing every vulnerable aspect of your platform. This is why we’ll explore four of the most common types of application security you’ll want to account for. With the help of software security testing tools and these 12 web app security best practices, you can secure each area accordingly.

 

Authentication and Authorization

When creating a web application, authenticating and authorizing your users is the first step to safeguarding your platform.

When authenticating, you’ll want to verify a user's identity, ensuring they are legitimate and not trying to hack anyone’s account. Authorization, on the other han,d looks at the permissions or access levels the user is entitled to, as this can affect what they are allowed to do on your app.

Robust authentication and authorization measures can positively impact your platform. Not only will it help prevent attackers from accessing the platform, you'll also be able to keep sensitive information safe from prying eyes.

Best Practices to Authenticate and Authorize Users:

1. Implement Multi-Factor Authentication (MFA)

Single password authentication methods make applications highly vulnerable to attacks and phishing. Using MFA is a great way to add extra protection in the verification process, minimizing attempts at unauthorized access to an account or the platform.

The beauty of multi-factor authentication is its ability to provide different methods to verify users before granting them access to information or your app. Offering a combination of passwords with one-time codes or even biometrics can make it harder

Pro Tip: Adaptive MFA can adjust your authentication requirements easily based on information that can impact risk, such as the type of device used, the user’s location, or their general behavior when using your application.

2. Utilize OAuth 2.0 for Secure Authorization

Instead of storing user passwords that can make your platform vulnerable to credential leaks, build OAuth 2.0 into your list of web app security best practices. Tokens are used instead of traditional password storing by using access tokens. Since tokens have restricted use, this makes it harder for an attacker to hack data.

OAuth 2.0 is a recognized standard security protocol that uses third-party services and saves you from exposing your user’s credentials. If you haven’t implemented this yet, it’s high-time to get on it.

Pro Tip: Tokens with short lifespans and refresh tokens are key to keeping exposure at bay.

3. Enforce Least Privilege Access

Least privilege may seem like an over-exaggeration to the untrained eye, but this can save your user data and minimize any damage an attacker might inflict on the compromised account.

Enabling any type of user or account to access more controls and data than necessary can increase the chances of a successful attack. If an account is hacked, all existing sensitive data can be stolen, or they may exploit permissions.

Pro Tip: Build regular reviews and updates into your processes or automation for role-based access control.

Injection Flaws

Injection flaws happen when untrusted data is shared with an interpreter for a specific task or query. If unnoticed, attackers can embed malicious code into your platform to access private information. Some usual places they appear are in SQL, NoSQL OS, and LDAP.

Best Practices to Prevent Injection Attacks

4. Use Parameterized Queries

Defining all SQL code for queries allows your database to distinguish what is code and actual user input.

SQL injection is a well-recognized vulnerability developers and cybersecurity teams need to watch out for. Enforcing prepared statements and parameterized queries can be your best defense against it as it separates data from SQL logic.

If any malicious code attempted to be fed in using parameterized queries in your web application best practices will ensure the database won’t actually recognize the command, dodging any breach.

Pro Tip: Dynamic SQL isn’t the best option. Parameterized queries for even the smallest tasks like dropdown selection can strengthen the safety of your app.

5. Sanitize Data

Filtering data isn’t an effective way to prevent injection attacks. Attackers will more often than not manipulate URLs and form inputs to plug in their malicious code.

Incorporating the right data sanitation practices can make a big difference in preventive measures. You can do this by limiting the special characters to prevent any attempts at concatenation. Typecasting data to restrict the data format from specific fields can also work.

Pro Tip: Approach sanitization with a whitelist approach so that you can be more explicit in your defined characters and input formats.

6. Employ Object-Relational Mapping (ORM) Frameworks

Object-Relational Mapping allows developers to use databases with programming language instead of going through the tedious process of using raw SQL.

ORM essentially lets you protect your platform against injection attacks with automated parameters to sanitize your data. It’s the best of both previous best practices, binding inputs as parameters, preventing code interruption.

Pro Tip: Always update your ORM library to prevent new vulnerabilities from impacting your app.

Logic Flaws

When attackers are able to gain control of an app because of it’s design, business logic, or operational flow, they can breach data or exploit functionalities of the platform. This type of flaw can be different for every application and its intended functions. Attackers will most likely need to understand your business’s domain or how your app works.

Any small gap in the assumption of a user’s interaction can effectively leave your application vulnerable.

Best Practices to Prevent Attacks on Design and Logic Flaws

7. Conduct Thorough Threat Modeling

Proactively anticipate any logic flaws with threat modeling. Your cybersecurity team can analyze workflows and exercise thinking like a hacker to spot weaknesses before you start coding.

Pro Tip: You don’t have to limit analysis to security, include cross-functional teams like developers, QA, and your business analyst to factor in every possible threat or vulnerability so you can start building strong.

8. Stick to Strict Input Validation

When input validation isn’t made to adhere to a set of formats and values, attackers might take advantage of your processes. Every form, API, and so on should be sanitized and validated accordingly.

Additionally, you can put a rate limit and CAPTCHA to prevent just anyone from conducting one too many actions. Matching this with session expiry and token refreshes can help manage use of your platform too.

Pro Tip: Always use server-side validation to maintain input integrity even before you get the chance to process your data.

9. Conduct Machine Learning (ML) and AI-Backed Security Testing

When you conduct your security testing, it pays to use web app security tools that have AI-powered detection when screening user activity. ML and AI features can not only learn from historical data, it can also spot loopholes for detect threats that are constantly evolving to prevent data breaches and attacks on logic flaws.

With the right security system in place, you can automate all necessary prompts, alerts, and procedures as soon as suspicious behavior is detected.

Pro Tip: Fuzz testing tools can help you catch any unexpected user behaviors.

Exposure of Stored Sensitive Data

Sensitive data is a valuable asset for any business, especially retail ERP systems. It can include a user’s personal, financial, and health information, or for your business’s case, trade secrets and intellectual property. The exposure of this stored data will not only impact your operations and reputation, but can put all your users at risk.

The exposure of data can be a result of many factors that range from misconfigurations, device theft, to lack of encryption.

Best Practices to Prevent Exposing Sensitive Data

10. Encrypt Sensitive Data at Rest and in Transit

Unencrypted data is like stealing candy from a baby to attackers. Encryption is the best way to protect data as it keeps information unreadable to any unauthorized user.

Open Web Application Security Project (OWASP) recommends using regularly updated algorithms to secure encryption whether it’s at rest or in transit to keep it useless from hackers.

Pro Tip: Look for encryption libraries that support Perfect Forward Secrecy (PFS). They help you avoid past communications from getting decrypted in the event the information is compromised.

11. Implement Access Controls and Data Masking

Restriction is a good way to prevent access to sensitive data. In this way, you can ensure only authorized users or accounts can handle the information. Whenever possible, allow activity only based on user roles and responsibilities.

Data masking techniques can obscure any sensitive data in events where data visibility isn’t required, reducing the chance of exposing data and having it misused.

Pro Tip: Use format-preserving encryption to maintain usability of secured data.

12. Regularly Audit and Monitor Data Access

Tracking the history of who’s accessed and used sensitive data is imperative. Using an ongoing monitoring system is the most efficient way to oversee and log data usage. They can detect unauthorized access in real-time and help you manage data controls better.

Periodic audits are also useful in identifying security gaps to check for compliance on data protection policies too.

Pro Tip: Test cryptographic modules to check for configuration effectivity and verify that controls function effectively.

Conclusion

No matter your business’s industry, ensuring your platform is well-protected matters. There are many cyberthreats that evolve with AI’s advancements, making it more sophisticated and more challenging to detect. Fortunately, conducting a secure web application development process can make all the difference in maintaining your business’s operations, reputation, and user protection.

When you factor in the different areas of vulnerabilities, you can create a robust security program that can minimize any attempted data breaches.