Why This Issue Is Important
When a flow variable that can be easily tainted by user input (such as the Host header or proxy.url) is used to influence subsequent request processing logic, it introduces a significant security risk. Attackers can manipulate these variables to circumvent intended processing logic, potentially leading to unauthorized access, data leaks, or other unexpected behaviors.
How This Issue Is Detected
CodeSent scans the flow to identify variables that are known to be influenced by user input, such as request.header.host and proxy.url. The tool traces the flow of these variables to see if they influence other flow variables or are used in subsequent processing steps. If such a variable flows into another variable or processing step without proper validation, CodeSent flags this as a potential risk.
How to Fix the Issue
To fix this issue, you should avoid using user-controlled variables like the Host header or proxy.url directly in your processing logic. Instead, use more secure variables like virtualhost.aliases, which are less prone to tampering.