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6 Web Application Vulnerabilities and How to Prevent Them

One of the biggest fears for development managers is not identifying a vulnerability in their web application before an attacker finds it. Web application vulnerabilities leave you susceptible to security attacks during which valuable customer and company data could be at risk. As a result, you will incur huge financial losses while your reputation suffers serious damage.

The good news is that these web application security threats are preventable. roper knowledge of the most common web application vulnerabilities is the key to prevention. While you may conduct automated scans and regularly test for any web application vulnerabilities, those efforts will be in vain unless you know what to look for.

This makes it crucial to understand web security vulnerabilities inside out – right from how a web application gets targeted to what kind of vulnerabilities to look for and how to prevent them. This post is going to help you do exactly that.

How Web Application Vulnerabilities Affect Companies

First, let’s try to gain a better understanding of how exactly these website application vulnerabilities can affect a company. This will help you understand just how harmful these security attacks can be and why you should prioritize preventing them.

One of the biggest, most harmful web application security threats is sensitive data exposure. It even ranks among the OWASP top 10 vulnerabilities. It involves compromising important data that should have been protected. This includes data like passwords, credentials, personally identifiable information, social security numbers, credit card numbers, health information, etc.

This is one of the most targeted web application vulnerabilities by hackers since there’s a prospect for financial gain for them. They could sell this data or use it themselves to conduct fraud, identity theft, etc.

There are tons of ways for hackers to steal sensitive data through web security vulnerabilities:

They may look for SQL injection flaws to retrieve decrypted credit card numbers.
They could exploit insecure wireless networks to seal a user’s session cookie.
Attackers could even retrieve sensitive files from the server using a file download vulnerability, or upload malicious files to target your users!
In some cases, you may even encounter Cross-Site Scripting (XSS). This is one of the most widespread website application vulnerabilities and involves utilizing the website as a propagation method. Hackers would inject malicious client-side scripts and modify how the website functions or how it is displayed.

An XSS attack could infect your visitors’ devices with malware or have them recruited into large botnets. It could mislead your visitors and damage your credibility and reputation, which can be extremely difficult to rebuild.

These are just a few ways in which hackers can exploit web application vulnerabilities and cause serious harm to your company and its customers. But even from this, you can clearly see just how damaging these attacks can be and how crucial it is to prevent them. We need to take web application security threats seriously and turn our development teams into security champions.

Understanding the Common Web Application Vulnerabilities

Now let’s take a look at some of the most common attacks that hackers might attempt on your website. Knowing these common web application vulnerabilities will help you identify them faster and fix them more easily.

1: SQL Injection

Many hackers start with an attempt to gain access to the database through SQL injection attacks. This is when the attacker inserts malicious SQL statements into form fields and other injection points, with the intention of gathering information from and controlling the database. They can use this information to access and modify or even destroy the information, and to attack the underlying system.

Attackers typically use these attacks to collect vital customer information such as their contact information, passwords, or even credit card info. They may even exploit these web security vulnerabilities to change the price of a product, for instance. Advanced attacks can even allow them to control the database server and the operating system.

How to Prevent It

Prepared statements with parameterized queries can mitigate SQL-related web application vulnerabilities. A prepared statement helps to sanitize the input and ensures that it is considered as a string literal in SQL rather than as part of the SQL query. In other words, the database can tell the difference between SQL data and SQL code. So the code is no longer vulnerable to SQL injection attacks as the query is less vulnerable to tampering.

Migrating to Object Relational Mapping Tools (ORMs) is another excellent option. However, most ORMs allow non-parameterized queries in addition to performing parameterized queries. As such, it’s crucial to carefully use the frameworks keeping this in mind.

Make the most of LIMIT and other SQL controls within your queries so that even if an SQL injection attack does occur, it can prevent the mass disclosure of records.

2: Cross-Site Scripting (XSS)

As mentioned earlier, cross-site scripting or XSS is one of the most popular web application vulnerabilities that could put your users’ security at risk. These attacks inject malicious code into the running application and executes it on the client-side.

The goal of XSS attacks is to send this malicious code to other users, sometimes infecting their devices with malware or stealing sensitive information. This type of website application vulnerability can give the attacker full control of the user’s browser and can be extremely dangerous to any website.

How to Prevent It

Modern frameworks have made it a lot easier to escape untrusted user input and mitigate XSS attacks. AngularJS, React JS, and Ruby on Rails are some of the latest, most effective frameworks to prevent these web application vulnerabilities. These frameworks can automatically escape user input and help mitigate XSS attacks by design, although they do have limitations.

Avoid implementing a blacklist, instead favor of a whitelist, because blacklists are less effective at preventing web security vulnerabilities. An attacker who knows what they’re doing can easily bypass a blacklist filter.

The ultimate solution to prevent these web application vulnerabilities is output encoding. This involves converting untrusted user input into a safe form so the input is displayed to the user as data without being executed as code in the browser. This means that special characters will be translated into an equivalent form that the browser will no longer find significant.

It’s also important to understand that output encoding depends on the context of where data is being output. For instance, you may have HTML contexts, HTML entity contexts, HTML attribute contexts, CSS contexts, JavaScript contexts, and more. As such, you will need to apply context-sensitive encoding when render the page for the browser.

Enable a Content Security Policy (CSP), which can be very effective to help mitigate Cross-Site Scripting vulnerabilities.

3: Authentication Failure

Authentication-related web application vulnerabilities occur when there’s an improper implementation of adequate user authentication controls. This puts user accounts at risk of being breached. Attackers may exploit these web security vulnerabilities to gain control over any user account or even over the entire system.

One of these vulnerabilities is Credential Stuffing, where an attacker will test a list of valid passwords and usernames gleaned from another breach or attack until they manage to find a valid combination and gain access.

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