Every web application faces security threats.
These threats come from attackers who try to steal data, break systems, or misuse user information.
By understanding common security threats, developers can protect their JavaScript applications before problems happen.
Common Security Threats in JavaScript
- Cross-Site Scripting (XSS)
- Data Injection
- Broken Authentication
- Insecure Storage of Data
- Exposed API keys
- Clickjacking
- Session hijacking
Knowing these threats is the first step toward strong security.
This code allows malicious scripts to run in the browser.
An attacker can steal data, cookies, or user sessions using this method.
Using textContent ensures that user input is treated only as text, not as code.
This protects the application from XSS attacks.
These examples show how common security threats appear in simple code.
By understanding these risks early, students gain the ability to write safer, more secure JavaScript applications that protect users and build trust — a key skill for professional developers.