🔒 Fix path traversal vulnerability in HttpServer

[ManupaKDU]

🎯 What: Fixed a path traversal vulnerability in the ReturnFile method in Utilities/HttpServer.cs by ensuring that the resolved absolute path starts with the application's base directory.

⚠️ Risk: Without this fix, malicious users could send arbitrary paths (e.g. ../../Windows/System32/config/SAM) in HTTP requests and read any file on the filesystem that the application process has permissions to read. This would result in sensitive information disclosure.

🛡️ Solution: The method now constructs the expected root directory using AppDomain.CurrentDomain.BaseDirectory and normalizes the requested path using Path.GetFullPath(Path.Combine(...)). It checks if the requested path falls under the expected root directory and rejects requests that escape it with a 403 Forbidden HTTP status, eliminating the path traversal vulnerability.

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PR created automatically by Jules for task 16989806303177403089 started by @manupawickramasinghe

[google-labs-jules]

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