What is web application security?

Web application security is important to any business. Learn about common web application vulnerabilities and how they can be mitigated.

Learning Objectives

After reading this article you will be able to:

  • Learn the core concepts of web application security
  • Explore common web app vulnerabilities/exploits
  • Understand common methods of threat mitigation

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What is Web Application Security?

Web Application Security


What are common web app security vulnerabilities?

Attacks against web apps range from targeted database manipulation to large-scale network disruption. Let’s explore some of the common methods of attack or “vectors” commonly exploited.

  • Cross site scripting (XSS) - XSS is a vulnerability that allows an attacker to inject client-side scripts into a webpage in order to access important information directly, impersonate the user, or trick the user into revealing important information.
  • SQL injection (SQi) - SQi is a method by which an attacker exploits vulnerabilities in the way a database executes search queries. Attackers use SQi to gain access to unauthorized information, modify or create new user permissions, or otherwise manipulate or destroy sensitive data.
  • Denial-of-service (DoS) and distributed denial-of-service (DDoS) attacks - Through a variety of vectors, attackers are able to overload a targeted server or its surrounding infrastructure with different types of attack traffic. When a server is no longer able to effectively process incoming requests, it begins to behave sluggishly and eventually deny service to incoming requests from legitimate users.
  • Memory corruption - Memory corruption occurs when a location in memory is unintentionally modified, resulting in the potential for unexpected behavior in the software. Bad actors will attempt to sniff out and exploit memory corruption through exploits such as code injections or buffer overflow attacks.
  • Buffer overflow - Buffer overflow is an anomaly that occurs when software writing data to a defined space in memory known as a buffer. Overflowing the buffer’s capacity results in adjacent memory locations being overwritten with data. This behavior can be exploited to inject malicious code into memory, potentially creating a vulnerability in the targeted machine.
  • Cross-site request forgery (CSRF) - Cross site request forgery involves tricking a victim into making a request that utilizes their authentication or authorization. By leveraging the account privileges of a user, an attacker is able to send a request masquerading as the user. Once a user’s account has been compromised, the attacker can exfiltrate, destroy or modify important information. Highly privileged accounts such as administrators or executives are commonly targeted.
  • Data breach - Different than specific attack vectors, a data breach is a general term referring to the release of sensitive or confidential information, and can occur through malicious actions or by mistake. The scope of what is considered a data breach is fairly wide, and may consist of a few highly valuable records all the way up to millions of exposed user accounts.

What are the best practices to mitigate vulnerabilities?

Important steps in protecting web apps from exploitation include using up-to-date encryption, requiring proper authentication, continuously patching discovered vulnerabilities, and having good software development hygiene. The reality is that clever attackers may be able to find vulnerabilities even in a fairly robust security environment, and a holistic security strategy is recommended.

Web application security can be improved by protecting against DDoS, Application Layer and DNS attacks:

WAF - Protected against Application Layer attacks


DDOS How A WAF Works

DDoS mitigation

A commonly used method for disrupting a web application is the use of distributed denial-of-service or DDoS attacks. Cloudflare mitigates DDoS attacks through a variety of strategies including dropping volumetric attack traffic at our edge, and using our Anycast network to properly route legitimate requests without a loss of service. Learn how Cloudflare can help you protect a web property from DDoS attacks.

DNS Amplification DDoS attack animation

DNS Security - DNSSEC protection

The domain name system or DNS is the phonebook of the Internet and represents the way in which an Internet tool such as a web browser looks up the correct server. Bad actors will attempt to hijack this DNS request process through DNS cache poisoning, on-path attacks and other methods of interfering with the DNS lookup lifecycle. If DNS is the phonebook of the Internet, then DNSSEC is unspoofable caller ID. Explore how you can protect a DNS lookup using Cloudflare.