XSS web app attack

6 Most feared web application attacks and how to beat them – Part 3 (XSS)

Under this new digital era, an attack on the organization’s web application implies a destructive impact on the brand and its reputation. It can also lead to loss of customer trust and downfall in the share market. As per a study by the National Cyber Security Alliance, around 60 percent of small- to medium-scale enterprises (SMEs) go out of business after six months of well-planned cyberattacks. It indeed becomes challenging for an organization to recover from the ill-effects of cyberattacks.

“Cross-site scripting exploits dynamic web pages by introducing malicious scripts to trusted websites.”
Under this series of web application attacks, this time, we will be discussing cross-site scripting. These are one of the common forms of injection attacks. It can be described as an “injection of malicious scripts into trusted websites.” Well, the good news is that the well-planned precautionary measures can help in eliminating them. For instance, properly sanitized user input can help your organization to rid of the attack.

Commonly found web application attack – Cross-site scripting (XSS)

cross-site scripting attack

Cross-site scripting attacks disrupt the interaction between users and the vulnerable application. It is based on client-side code injection. The attacker inserts malicious scripts into a legit application to alter its original intention. The inserted code then piggybacks the altered scriptto the user’s web browser.These attacks are common in web applications written in JavaScript, CSS, VBScript, ActiveX, and Flash.

Which vulnerability can lead to cross-site scripting attacks?

Though the scripting language run in a very controlled environment, it can still be dangerous. Generally, malicious scripts are designed to gain access to all the objects, including user’s cookies, as they act as a key to store session tokens. So, if cyber attackers gain control over cookies, they can impersonate the targeted individual, retrieving their sensitive data.

With the integration of web application vulnerabilities and social engineering methodologies, attackers can execute advanced cyberattacks, such as cookie theft, planting trojans, keylogging, phishing, and identity theft.

How can you stop cross-site scripting attacks?

  • Data sanitization should be a mandatory process.
  • The input data should be scanned before it goes to the database server.
  • Encode output data so that it won’t appear as active content.
  • The use of appropriate headers will help in keeping the intention of scripts clear to the web browser.
  • Add another layer of protection against XSS attacks with the Content Security Policy (CSP). As per CSP, website administrators will have authority over user-controlled resources.

What are the skills required to combat XSS attacks?

Organizations need professionals with computer networking knowledge and an immense understanding of various scripting languages and web designing to combat XSS attacks. The professional also needs to have advanced penetration testing skills to identify potential vulnerabilities.

In our next blog, we will be covering the brute force attack. An exhaustive form of attack but still being in use. Learn how this time-consuming attack can become your worst nightmare.

Well, organizations with online businesses, especially the ones possessing web applications, require skilled professionals to keep their apps secure from cyber attackers. They need professionals with incredible penetration testing knowledge so that attacks can be prevented beforehand. For that, Licensed Penetration Tester (L|PT) Master is the best way to show your security skills. It is an 18-hour long hands-on exam which ensures that you have the skills to defend an organization from different types of attacks, including web application attacks.

Most organizations today have an online presence, so web applications are not a rare commodity. Keeping apps secure from these attacks is the need of the hour. Anyone considering a penetration testing certification is guaranteed to have a bright future. Sooner or later, every business is going to need a penetration testing professional to secure their infrastructure. As a junior ethical hacker, or an IT professional planning a career move, it makes sense to consider penetration testing to enter the next phase of your career.

So, what are you waiting for? Enroll now and start your career path as a penetration testing professional!


What is cross-site scripting example?
XSS is a client-side injection attack, where attacker execute malicious scripts in a targeted web browser. For instance, attackers send misleading emails with a URL. This link will redirect the target to a vulnerable web application, leading to security incident.

Read more: Most Common Web Application Attacks and How to Defend Against Them

What are the types of cross-site scripting?
There are three types of XSS attacks – Persistent XSS, Reflected XSS, and DOM-based XSS.

Read more: 4 Types of Cyberattacks That You’re Most Likely to Face

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