Web vulnerabilities are weaknesses in websites or web applications that can be exploited by attackers to gain unauthorized access or cause harm. Common types of vulnerabilities include SQL injection, where malicious code is inserted into a database query, and cross-site scripting (XSS), which allows attackers to inject scripts into web pages viewed by users. These vulnerabilities can lead to data breaches, loss of sensitive information, and damage to a website's reputation. To protect against web vulnerabilities, developers must implement security best practices, such as input validation and regular security testing. Tools like web application firewalls (WAFs) can help detect and block attacks. Staying informed about the latest threats and applying security patches promptly is essential for maintaining a secure web environment.