Organizations are rapidly moving towards web-based applications and services to run their business and connect with customers. From eCommerce platforms and customer portals to internal tools and APIs, web apps power essential services across every industry. But with this growing reliance comes a growing risk: cybercriminals are increasingly targeting web applications as a primary attack vector.

That’s why web application security is more important than ever. Failing to protect your applications not only exposes sensitive data but also threatens business continuity, customer trust, and regulatory compliance.

In this article, we’ll explain why application security is important, explore the benefits of application security testing, and share essential web application security best practices every organization should follow to stay protected in an ever-evolving threat landscape.

Why application security is important

As organizations increasingly rely on web applications to deliver services, manage data, interact with users and integrate with third-party systems, the attack surface has expanded significantly. Web apps are now one of the most common entry points for cyberattacks, with the risks growing rapidly.

According to the 2025 Verizon Data Breach Investigations Report, there has been a 34% year-over-year increase in exploited vulnerabilities in web applications since 2024. This sharp rise highlights how attackers are prioritizing poorly secured applications as high-value, low-resistance targets.

Web app attacks can have far-reaching consequences, from data theft and loss of productivity to reputational damage and legal liabilities. At the same time, web application attacks are becoming more sophisticated and common.

Web application security challenges

There are several reasons why web applications are increasingly difficult to secure:

1. Web applications are becoming ever-more complex

The use of open source components, third-party services, containers, microservices, and APIs has increased the attack surface of web applications. As web applications grow in complexity with more dependencies and moving parts, they are becoming more and more difficult to secure as attackers can exploit even a tiny flaw in the codebase to gain access to sensitive data.

2. The rise of DevOps and continuous delivery

Accelerated release cycles make it harder to find and fix security issues before deployment to production. Businesses release new features and functionality faster than ever, leaving little time for adequate testing and security hardening.

3. The always-on era

External web applications are built to be accessible from the internet and anywhere worldwide, 24 hours a day, 7 days a week. This makes Identity and Access Management (IAM) a critical security concern.

4. Web app sprawl and rogue apps

The ease of web application development has led to web app sprawl, making it challenging to keep up with penetration testing, patching, maintenance, and updates. There is also a widespread proliferation of “rogue” applications built by business users without the knowledge of IT and security teams. These applications are often inadequately tested and pose a significant security risk.

Benefits of application security testing

For any organization aiming to stay ahead of today’s cyber threats, application security testing is your best defense. This involves evaluating your web applications for vulnerabilities both during development and after deployment to ensure they can withstand real-world attacks.

Some of the key benefits of implementing a robust application security testing program include:

• Early detection of vulnerabilities: Security testing helps identify flaws (e.g. SQL injection, authentication issues, misconfigurations, etc.) early in the development cycle. Catching these vulnerabilities before production significantly reduces the cost and impact of remediation.
• Reduced risk of data breaches: Proactively testing your applications helps prevent the exploitation of common vulnerabilities that could lead to unauthorized access or data theft. This reduces the likelihood of incidents that cause financial losses, legal issues, and reputational damage.
• Compliance with industry regulations: Standards like GDPR, PCI DSS, HIPAA, and ISO 27001 require regular security assessments. Application security testing supports compliance efforts by making sure your systems meet security benchmarks and audit requirements.
• Brand reputation: By demonstrating a commitment to secure development, businesses build trust with customers, partners, and stakeholders. In competitive markets, being able to prove that your web apps are tested and secure can make all the difference.
• Continuous improvement and visibility: Security testing delivers detailed insights and metrics on your web app’s risk posture, which leads to better decision-making and easier prioritization of fixes.

Types of web application security testing

So, what’s the best way to secure your web applications? The answer is: it depends. There is no one-size-fits-all solution to web application security. However, there are a few popular approaches, which we’ll outline below.

Automated web application security scanning

Security must move at the speed of DevOps. That’s where automated DAST scanning comes in. These tools continuously test applications for common vulnerabilities like SQL injection, cross-site scripting (XSS), and other OWASP Top 10 issues.

The benefits of automated scanning include: 

• Scalability to test many apps simultaneously
• Continuous coverage without manual input
• Faster detection in Agile environments

However, automation alone isn’t enough. These tools can miss logic flaws and generate false positives, so they’re best used for low- to medium-risk apps or as a first line of defense.

Manual penetration testing

To go beyond automation, manual penetration testing is essential for effective web application security. This involves ethical hackers (white hats) attempting to break into a system to find security weaknesses. This can help you identify vulnerabilities that are not detectable by automated scanners, such as business logic flaws and authentication bypasses.

In addition, manual testing eliminates false positives generated by automated vulnerability scanners. This is important because web application security testing is often resource-constrained, and you need to prioritize your efforts on patching the most critical vulnerabilities first.

The downside of manual testing is that it’s time-consuming and expensive, and it can be difficult to schedule testing around Agile development cycles. Results can take time to deliver, and they may be outdated by the time they’re received.

Penetration-Testing-as-a-Service (PTaaS): Combining manual and automated testing

Securing your web applications is a never-ending task. You must prioritize your activities depending on the level of risk. In the age of agile development, combining automated scanning with manual pentesting is critical to successful web application security.

This might be challenging to do in-house due to the lack of resources (time, manpower, budget)—which is why a solution like Penetration Testing-as-a-Service (PTaaS) can be invaluable. This approach can help you get the most out of your web application security program by combining the benefits of automated scanning with the advantages of manual pentesting, delivered as an on-demand service.

PTaaS is a cost-effective way to get the benefits of both manual and automated web application security testing to secure your web applications, helping you protect your web applications continuously without having to invest in expensive security tools or hire dedicated security staff.

Best practices for web application security

1. Shift left

Fixing a vulnerability in production is infinitely more risky and expensive than fixing it during the development or testing stage. That’s why one of the most important best practices is to “shift left” by integrating security testing into the Software Development Life Cycle (SDLC).

By embedding tools like static (SAST) and dynamic (DAST) analysis into development and QA stages, organizations can detect issues before they’re deployed. This leads to faster remediation and lower costs.

2. Discover and map your attack surface 

You can’t secure what you don’t know exists. You’ll need to inventory all your internet-facing web applications, including those in development, staging, and production environments.

Using automated attack surface discovery tools can help you visualize your external attack surface, discover rogue apps and shadow IT, and identify potential security vulnerabilities in your web applications. This will help you determine which web apps need to be tested, as well as which need to be patched and updated.

3. Prioritize testing based on risk

Not all applications carry the same level of risk. For a security program to be effective, you need to prioritize web application security testing based on risk. Some factors to consider include:

• How sensitive is the data handled by the web app?
• How business-critical is the app?
• How frequent are release cycles and updates?
• What does your threat landscape look like?

Asking these questions helps make sure your most valuable—and vulnerable—applications receive appropriate testing coverage and remediation effort.

4. Avoid security misconfigurations

Security misconfigurations remain one of the most common (and preventable) causes of breaches. They occur when security settings are incomplete or left in default states, exposing your application to unnecessary risk.

Examples include:

• Unpatched software or outdated frameworks
• Default admin credentials still in use
• Overly permissive cloud storage or APIs
• Error messages revealing sensitive information
• Features enabled that aren’t needed (e.g. directory listing, debug mode)

To avoid these issues, you should conduct regular configuration audits across environments (development, staging and production), disable all unused features and services, and automate patching of dependencies and third-part components.

5. Implement continuous security testing

Security must be built into the SDLC from the very beginning. And to properly secure your live web applications, you need to monitor continuously for vulnerabilities and attack surface changes.

It’s important to remember that even if you fix a vulnerability today, new ones will crop up tomorrow. So it’s critical to have a continuous application security program that combines automatic scanning and manual pentesting to identify and fix vulnerabilities as they arise.

Take control of your web application security with Outpost24’s PTaaS solution

In a threat landscape that evolves by the hour, relying on point-in-time assessments is no longer enough. Outpost24’s Penetration-Testing-as-a-Service (PTaaS) solution, SWAT, gives you the continuous, real-time visibility you need to stay ahead of attackers.

Unlike traditional pen testing, SWAT is built for modern security teams and DevOps pipelines. It combines the speed and scale of automated scanning with the depth and accuracy of manual testing from certified ethical hackers. 

With SWAT, you get:

• Continuous monitoring and real-time insights of your vulnerabilities in a single UI
• Expert-verified findings to eliminate noise and focus remediation
• On-demand testing aligned with your release cycles
• Scalable coverage tailored to your risk profile and compliance needs
• Zero false positives

Want to know more? Book a live demo today to see how PTaaS can elevate your application security program with continuous, expert-led penetration testing.