What Is a Cross-Site scripting (XSS) Attack?

If your business operates one or more websites, it could be susceptible to a cross-site scripting (XSS) attack. While XSS attacks have been around for over a decade, they’ve become increasingly common in recent years. In fact, research shows approximately half of all cyber attacks targeting business websites involve XSS. To better protect your business from this common cyber threat, though, you must first understand how XSS attacks work.

The Basics of XSS Attacks

An XSS attack is a type of cyber threat that involves the injection of a malicious script into a website’s source code. During the attack, a hacker uses a web application to upload the malicious script to the targeted website where it’s then routed to visitors and or other users.

XSS attacks are concerning because they don’t just harm the targeted website; they harm the website’s visitors and users. The targeted website may represent a legitimate business — featuring all the appropriate trust signals. If it’s infected with a malicious script, though, anyone who visits the website could have their personal information stolen.

Persistent vs Non-Persistent XSS Attacks: What’s the Difference?

XSS attacks can be categorized as either persistent or non-persistent. Non-persistent XSS attacks are the most common. They occur when client-side data, such as HTTP requests, are used on the fly by a server-side script to generate content for a website or web page. In comparison, persistent XSS attacks are more rare. With a persistent XSS attack, the malicious script uploaded and injected by the hacker is stored on the targeted website.

How to Protect Against XSS Attacks

To protect against XSS attacks, you must focus on enhancing your business website’s security. For starters, this means choosing a reliable web hosting server that offers its own safeguards to protect against cyber threats, including XSS attacks.

There are more technical ways to protect against XSS attacks, such as filtering user input. If you filter user input based on its validity, visitors to your website will only be able to submit valid code. As a result, hackers won’t be able to submit — e.g. inject — a malicious script into your website.

In Conclusion

Millions of business websites are hacked each year. While hackers use a variety of cyber attacks against websites, one of the most common is XSS. During an XSS attack, a hacker will inject a malicious script into the website’s source code. The script may then perform a variety of malicious activities, such as capturing visitors’ data or distributing malware to visitors who browse the targeted site.