What Are The Most Common Attacks On Web Applications?

The best way to secure your web application is to know the threats that you’re up against. The landscape of web application attacks is constantly evolving, but there are several attacks that are the most common.

Successful attacks can not only steal your application’s data, but they can lead to costly lawsuits and tarnish your brand’s reputation. Understanding the most common application attacks is the first step to fighting them.

1. Brute Force Attack

We’re going to start off by talking about brute force attacks. These attacks are also commonly known as password hacking. In its most simple form, this is when hackers attempt to randomly guess computer passwords until they discover the correct password.

Even the most robust passwords can be brute forced when hackers employ a sufficiently powerful software engine. With this technology, hackers can make thousands of guesses per second.

Hackers typically don’t have to resort to randomly guessing passwords. Passwords using common terms like birthdays, sports teams, or the classic “password,” all make the guessing game much easier.

2. Zero-day Hacks

In the world of application design, the day new updates are sent out is typically called “day one.” Hackers with advanced knowledge of updates can slip in before “day one” and execute a zero-day attack.

These attacks actively take advantage of flaws in your web applications before you can patch them out. The severity of the hack doesn’t always have to correspond to the severity of the flaw. Even a minor vulnerability could turn into a serious data breach in the hands of an experienced, and dedicated, hacker.

3. Injection Attacks

Injection attacks seek to enter malicious commands to your web application’s servers. The two most common types of injection attacks are SQL injection attacks and OS command injection.

SQL injection attacks attempt to send a malicious script containing several SQL commands to your server through your web application. Common attack vectors are user data entry fields like prompts for usernames and passwords. Web applications typically store vital data on their servers which makes these attacks especially useful for hackers.

OS command injection is very similar to SQL injection. This hack sends malicious operating system commands directly to the server. If successful, these commands could do everything from send sensitive data to hackers to expose other systems connected to the same server.

4. Fuzz Testing (Fuzzing)

Many of the tools that hackers use to find exploits in web applications are also the tools that web application security experts use to locate vulnerabilities. Fuzzing, which gets its name from fuzz testing, is one of these tools.

Fuzz testing is the process of overloading a web application with random data. This will cause the web application to crash, and the dev team can use that crash report to find vulnerabilities in their systems. However, a hacker can also use fuzz testing to crash a web application and find the same vulnerabilities, but for a malicious purpose.

5. Cross-Site Scripting (XSS)

Cross-site scripting is one of the most common web application attacks. In this attack, a hacker uploads malicious code to a vulnerable website and that code is unintentionally activated by users of that website.

One of the reasons cross-site scripting is so popular is because it’s a very simple attack to execute. Cross-site scripting doesn’t require the same kind of specialized computer knowledge or hacking software as other attacks. This hack also attacks users directly rather than attacking the web application itself.

Cross-site scripting can be used for everything from session hijacking to stealing user data. Cross-site scripting is particularly dangerous in corporate settings where a successful cross-site scripting attack can give a hacker access to an entire network.

6. Denial-of-Service & Distributed Denial-of-Service

The goal of a denial-of-service attack is to send a massive wave of traffic to a web application with the goal of crashing or disrupting its usual operations. These attacks are often executed in a “distributed” fashion by networks of computers running “bots” that handle the attacks for them.

It’s a common misconception that denial-of-service attacks are just “pranks.” These attacks can cost corporations thousands, or millions, of dollars. This is especially the case for corporations using volume-based cloud services that charge based on the amount of traffic.

Hackers can also use a denial-of-service attack to distract web application security team members while they execute another attack on a vulnerability.

7. Path Traversal

Path traversal isn’t the most common attack on this list, but it could be disastrous if successfully executed on your web application.

Path traversal targets the root web folder. It attempts to use movements through the hierarchy of folders in your web application in order to access folders that are above the root folder in this hierarchy. This attack is often combined with other attacks and exploits in order to steal data and credentials from your web application.

The best way to fight path traversal is to sanitize your inputs wherever users interact with your application.

8. Man-in-the-Middle Attack (MITM)

Man-in-the-middle attacks are often seen as a bit old school, but they’re still incredibly effective at stealing unencrypted data.

A man-in-the-middle attack intercepts data that is passing between a user and a web application. The weaker the encryption is on this data, the more successful the man-in-the-middle attack is going to be.

The fastest way to combat a man-in-the-middle attack is to install a Secure Sockets Layer (SSL) certificate on your web application.

9. Phishing

Phishing is the most successful, and the most common, type of social engineering hack. These are hacks that don’t target the web application, or the servers, but target individual people themselves.

Phishing is typically done by sending fraudulent emails that attempt to get people to give up sensitive information such as passwords. A successful social engineering hack could have key players in your dev team giving up sensitive information without a hacker ever needing to exploit a vulnerability in your application.

Social engineering hacks are some of the most difficult to combat, but proper education for your team is the best place to start.