⚔️ Cross-Site Scripting (XSS): When Hackers Inject Code Into Websites
Cross-Site Scripting, or XSS, is one of the most common and dangerous web vulnerabilities. It allows attackers to inject malicious code into trusted websites — and it often targets users, not servers.
🧠 What Is XSS?
XSS (Cross-Site Scripting) is a type of attack where hackers inject malicious JavaScript into webpages. When other users visit the page, the script runs in their browsers — stealing data, hijacking sessions, or redirecting them to fake sites.
🎯 How It Works
- A website accepts user input (like a comment or search box)
- The input isn't properly validated or sanitized
- The attacker injects a script (e.g.,
<script>stealCookies()</script>) - When another user visits the page, the script runs in their browser
- The attacker gains access to sensitive data or control
🔥 What Can XSS Do?
- 🥷 Steal cookies, tokens, and login sessions
- 📥 Log keystrokes or capture user input
- 🔁 Redirect users to malicious websites
- 📦 Deliver malware through browser-based attacks
🧪 Types of XSS
- Stored XSS – Malicious code is saved in the database and shown to all users
- Reflected XSS – The script is in a URL and runs when the user clicks it
- DOM-based XSS – The vulnerability exists in the client-side JavaScript
🛡️ How to Prevent XSS
- 🚫 Sanitize user input (remove dangerous characters)
- ✅ Validate input and output correctly
- 🔐 Use Content Security Policy (CSP) headers
- 🧪 Escape HTML, JavaScript, and URL output
- 🧰 Use security frameworks with built-in XSS protection
✅ Final Thoughts
XSS attacks are sneaky and dangerous — not because they break into servers, but because they exploit trust between users and websites.
Every input box is a potential entry point.
Secure your code. Protect your users.
Tags:
CyberAttaque