Application Security

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Application Security Definition

Application Security refers to the steps businesses take to identify, repair, and protect applications against security vulnerabilities. This includes the work administrators and application security engineers do to better understand why applications expose vulnerabilities to exploitations in security and how to make them safer in the future.

Diagram depicts the layer structure of Avi's Application Security firewall.
FAQs

What is Application Security?

Administrators, application security engineers, and others are tasked with web application security work to keep sensitive data confidential. They also maintain the integrity of all data while keeping it appropriately accessible, and protect it from modification by even genuine users. These goals require application security testing professionals to identify several things:

  • their organization’s critical assets;
  • all authorized users and their levels of access; and
  • any potential application vulnerabilities, and weakness in the data or source code.

They can then develop any remediation measures that may be appropriate. Assessing security threats in real-time, repairing security flaws, conducting penetration testing, and improving software security might all be part of the work of an administrator tasked with application development and security.

What are Application Security Risks?

Web application security challenges vary, from large-scale network disruption to targeted database manipulation. Here are some examples of application security risks:

  • Cross site scripting (XSS) is a vulnerability that enables an attacker to inject client-side scripts into a webpage. This allows the attacker to access critical information directly from the user. For example, an attacker may identify such a vulnerability on an e-commerce website, and embed HTML tags in the comments. A comment can then lead users to files that can steal visitor session cookies on another site—giving them access to anything from credit card numbers on down.
  • Denial-of-service (DoS) and distributed denial-of-service (DDoS) attacks enable remote attackers to overwhelm a targeted server or the infrastructure that supports it with various kinds of traffic. This illegitimate traffic eventually denies service to real users, shutting the server down.
  • SQL injection (SQLi) is a technique attackers use to exploit vulnerabilities in databases. Specifically, these attacks can reveal things like user names and passwords, or allow attackers to manipulate or destroy data, or to modify or create user permissions.
  • Cross-site request forgery (CSRF) is a technique hackers use to impersonate authorized users after tricking them into making an authorization request. Obviously high-level users are frequent targets of this technique, since their accounts have more permissions, and once the account is compromised, the attacker can remove, modify, or destroy data.
  • Memory corruption occurs when bad actors use various attacks on an app, eventually modifying some part of its memory accidentally. The result is unexpected behavior or failure of the software.
  • Buffer overflow happens when attackers inject malicious code into the defined memory space of the system. Overflowing the capacity in the buffer zone causes nearby portions of the app’s memory to be overwritten with data, creating potential vulnerabilities.
  • Finally, like anything else containing sensitive data, an app is vulnerable to a data breach.

Web Application Security

Application security best practices protect your business and your customers. To understand the basics of application security and how it can preserve your reputation, keep these application security fundamentals in mind:

  • Application security testing tools such as web vulnerability scanners can help reveal potential application security vulnerabilities.
  • A web application firewall or WAF serves as a barrier between the server and the world, protecting the web application against harmful HTTP traffic. The WAF can help guard against some kinds of attacks, such as cross site scripting, cross site forgery, and SQL injection.
  • DDoS mitigation strategies use system and application security tools to properly route legitimate requests without any drops in service and shake volumetric attack traffic at the perimeter.
  • Protect your online app’s domain name system or DNS from man-in-the-middle attacks, DNS cache poisoning, and other DNS lifecycle problems with comprehensive application security.
  • Automated web application security scanners only identify vulnerabilities that are technical, such as cross-site scripting (XSS), SQL injection (SQLi), and remote code execution. Conduct a manual audit as well to ensure your web application is functioning, and to identify vulnerabilities in the user experience and logical interface.
  • Ensure your web server is also secure using the latest best practices, because attackers can approach your web application through your server. Do this by limiting remote access, eliminating unnecessary functionality, segregating data, installing security patches, and tailoring user permissions.

Web Application Security Breach

Web application security breaches can be very profitable for cyber criminals. These data breaches are often deployed stealthily and can go undetected for months, exposing customers’ personal records and causing last damage to businesses’ infrastructure and reputation. Monitoring web application security threats are critical to detecting signs of a web application security breach as soon as possible. Signs of a breach include: application malfunctioning and/or slow down; unexpected log messages, new jobs or users, and/or altered files; browser warnings; and customer complaints via help desk emails or social media.

Diagram depicts the layer structure of Avi's Application Security firewall.

Web applications are now the top target for attacks and breaches for large corporations. And getting hit with a web application security breach can cost millions.


In the event of a web application security breach, IT security teams should be equipped with a well-defined incident response plan. This includes:

  • Identification: It is crucial to ensure that all breaches and their sources have been correctly identified. This can be accomplished by confirming that attack validation checks are correlated to ensure there are no false positives, detection mechanisms understand all application aspects, logs and reports capture and highlight anomalies, and WAF filter rules and software are updated frequently.
  • Containment: Mitigate the impact of the breach by first creating a backup of the entire store of data on the affected web server. Then check all other services running on the machine hosting the web server to determine if the exploited vulnerability is an isolated incident or not. If possible, physically disconnect the system from which the attack originates.
  • Eradication: Once the threat source has been identified, eliminate the root cause of the breach by updating compromised passwords, remove the network channel and OS backdoor that facilitated the attack, and run the affected system through antivirus and malware tools.
  • Recovery: Replacing the hacked/defaced page with a clean page with a temporary message and and restore affected data using the backup.
  • Lessons learned: Web application security is an extremely valuable investment that requires ongoing maintenance. Every tier of a workforce, from the top down, should be aware of cyber security and familiar with a well-defined disaster recovery plan.



Enormous web application security breaches have affected some of the biggest, high-profile corporations in the world, compromising the data of millions of customers. As more businesses incorporate cloud based computing and use web applications to store and process data, web application security has become of the most significant areas of data security.

Why Application Security is Important

All businesses must address application security risks that could compromise their sensitive data, because damage from breaches is extreme and sometimes permanent. Application security is among the biggest targets for data breaches, and the state of application and particularly mobile security is in flux as technology changes and businesses struggle to keep pace with it.

As more companies move their apps and sites online, information security generally will become even more complex, and critical. This means application security technologies will grow ever more crucial to the security of business, the apps that run companies, and their data security.

Network Security vs Application Security

It’s a common web application security myth that a network firewall can protect websites and web applications behind it. However, network and application security are not the same.

Network security uses perimeter defenses such as firewalls to keep out bad actors and grant access to safe users. For example, administrators can configure firewalls to permit only specific users or IP addresses to access particular services.

However, these perimeter network defenses are not enough to guard web applications against malicious attacks. This is because web applications and business sites must be accessed by everyone. Traffic coming to and from web applications therefore can’t be analyzed by network firewalls, so they can’t block malicious requests. If bad actors want to exploit a vulnerability such as a Cross-site Scripting or an SQL injection, network security won’t help.

Web application security tools like network security scanners can help identify certain problems that network security systems miss—specific web application security issues like SQL Injection problems. Application security testing tools can scan all components of your app to ensure they are fully patched. For example, such a tool might alert an administrator if an FTP server allows anonymous users to write to it.

Cloud Application Security vs Web Application Security

A cloud application and a web application may be very similar, but they are not identical. A cloud app is used to access online services, but not necessarily using a web browser.

Typically, a cloud app is custom-built for cloud use, and often optimized for mobile. Its data is stored online in the cloud, cached completely for offline use.

This may mean the cloud app has different permissions or user needs to accommodate—and different application security issues to manage. Mobile apps are mostly cloud apps.

Web applications rely more heavily on the web browser and whatever security measures are in place to protect it. Cloud applications are web apps; you can use them with web browsers. However, not all web apps are cloud apps.

What is Web Application Security Software?

Web application security software is an appliance or software package configurable by the user that is designed to ensure a secure web application. A web application firewall or WAF is one example of web application software.

Unfortunately, all web application firewalls—like all other application security software packages and application security tools—depend on the user. No mobile application security measures will function properly if they were not configured correctly.

What is the best way to go About Improving Web Application Security?

Web application security testing is a critical part of managing any app. Follow the best application security principles to improve your outlook, and get expert help creating a plan for your app.

How does Avi Networks help with Application Security?

Avi’s Intelligent Web Application Firewall (WAF) provides an application security solution in three critical steps: inspect, inform, and mitigate.
Inspect – The system analyzes user-to-application traffic and security configurations constantly. This allows it to identify vulnerabilities, and detect anomalies and attacks before it’s too late.

Inform – Next, Avi’s WAF tells your key staff about the security status of your apps in real-time with logs, alerts, and simple metrics that reflect risks.

Mitigate – Finally, the WAF system allows you to proactively work against security problems, from simple to serious. Implement whatever action is necessary, from simple penalties to limits on traffic or blocks to specific users.

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