Cross site scripting (XSS) is a pesky software weakness often lurking in web applications. It’s like an open window that lets online baddies sneak in and cause mischief.

What does XSS do? Well, it allows cyber crooks to slip sneaky scripts into pages viewed by other users turning harmless sites into digital traps for unsuspecting visitors. They can even use it to overwrite access controls (yikes!). If the network admin or website owner doesn’t put up the right security measures, XSS can become a major risk.