What is cross-site scripting?

XSS attacks target the code (otherwise known as the script) in a web page that is executed in the user's browser, rather than on the website’s server. When you’re attacked, your browser is injected with malicious scripts that will try to harm your computer. There is an almost limitless variety of XXS attacks but most try to harvest personal data, redirect victims to websites controlled by the hacker or make your PC perform operations on behalf of the hacker.

Cross-site scripting - XSS
How do XXS attacks happen?

Websites store data and send information to your browser all the time: XXS attacks happen when untrusted sources send users malicious content via vulnerabilities in the websites to your browsers that will then go on to steal your data or harm your PC. For example: when a user searches for something online, the website will then send information to the browser in the form of search results. In a XXS attack, the information they send back can contain malware that might steal your data. Because nearly every website requires storing and sending data to browsers, XSS is the most common security vulnerability in software today.

How can you recognize a XXS attack?

Unfortunately, your browser has no way of knowing if a script should not be trusted and will automatically execute any scripts it receives. This means that malicious scripts can access any sensitive information that the browser has stored, or has saved on the webpage. This makes XXS attacks pretty much impossible to recognize.

How can you remove XXS vulnerabilities?

It’s the job of the owner of the website to find and remove XXS vulnerabilities since that’s where the malicious code lurks, infecting unwitting visitors. Asking people to protect themselves by avoiding suspicious websites doesn’t work in this case as these vulnerabilities affect all websites, trusted and untrusted ones alike. Fortunately, there are tools online you can download to scan websites to check for XXS vulnerabilities.

How to prevent a cross-site scripting attack
  • Install top-rated antivirus software on your computer
  • Set your software settings to update automatically
  • Download a scanner which can check for vulnerabilities in a website’s code
Protect yourself against a cross-site scripting attack

In order to protect yourself from an XXS attack, it’s not enough to avoid untrusted websites. To keep any infections from spreading onto your PC and doing untold damage to your machine or stealing your data, it’s good to have a top-rated antivirus installed, such as Avast Antivirus.

Why Avast?
  • Consistently rated “excellent” by industry experts
  • Trusted by 400 million people worldwide
  • It’s the "Antivirus with the lowest impact on PC performance” (AV comparatives)
  • Best features - unbreakable password security, home network protection, browser cleaning and much more
  • All for FREE