Fundamentals of Secure Software - Cross-Site Scripting

The video tutorial explains cross site scripting (XSS), a security vulnerability in web applications that allows attackers to inject scripts into web pages. It covers two types of XSS attacks: reflected and persistent. Reflected XSS involves attackers creating a malicious URL to steal information, often using social engineering. Persistent XSS involves inserting a script into a website's database, affecting all users who view the page. The tutorial emphasizes the importance of input validation to prevent such attacks.

What is a primary reason that Cross Site Scripting (XSS) vulnerabilities occur in web applications?

• Improper validation of inputs from the web browser

• Excessive use of encryption

• Over-reliance on server-side scripting

• Lack of user authentication

In a reflected XSS attack, how does an attacker typically trick a user into clicking a malicious link?

• By hiding the link in a QR code

• By embedding the link in a downloadable file

• By sending the link through a secure channel

• By using social engineering tactics

What is a key characteristic of a persistent XSS attack?

• The script is executed only once and then removed

• The attack requires physical access to the server

• The attack is only effective during a user's session

• The malicious script is stored on the server and affects all users who view the page

How do attackers typically insert malicious scripts in a persistent XSS attack?

• By exploiting a vulnerability in the server's operating system

• By using legitimate means like forms or product reviews

• By hacking into the server's database

• By sending phishing emails to the server administrator

What happens when a user views a page affected by a persistent XSS attack?

• The malicious script executes and sends data back to the attacker

• The page fails to load

• The user's browser crashes

• The user is redirected to a different website