🔒 XSS Vulnerability in Development Config Exposes Potential Attack Vector

A high-severity Cross-Site Scripting (XSS) vulnerability has been identified within a critical development configuration file. The flaw resides in a `document.write` call that directly incorporates user input without proper sanitization, creating a potential injection point for malicious scripts to execute in users' browsers. This type of vulnerability is classified under OWASP's A03:2021 - Injection category and represents a significant security risk if exploitable in a live environment.

The affected file is `config/env/development.js`. On line 11, the code constructs a script tag for live reload functionality by concatenating the `location.host` property. This practice of dynamically writing script tags with unsanitized input is a textbook XSS vector. While the current confidence in exploitability is rated at 40%, the presence of such a pattern in a configuration file underscores a lapse in secure coding practices that could be replicated elsewhere in the codebase or misconfigured in a deployment.

The discovery prompts immediate scrutiny of input handling mechanisms across the entire application stack. It signals a need for rigorous code review to identify similar unsafe patterns and enforce the use of context-appropriate escaping functions. For development teams, this serves as a critical warning: security vulnerabilities can originate in foundational configuration scripts, not just application logic. The recommended mitigation is to eliminate the direct use of `document.write` with user input and implement standardized sanitization libraries to prevent such injection risks.