Exploiting vulnerabilities is necessary to inject malicious scripts into a website. These vulnerabilities can be in the website's code, server configuration, or user inputs. Hackers may use several methods to achieve code injection, such as Cross-Site Scripting, SQL Injections, and File Upload Vulnerabilities. Remote File Inclusion, Server-Side Template Injection, and Content Management System Vulnerabilities are other potential strategies. Web developers and administrators have to follow secure coding practices to ensure that websites are not compromised by malicious code.