Bug Report: Unhandled exception "AttributeError: 'NoneType' object has no attribute 'replace'" (#1925bfc9)

[commixreporter]

Commix version: 4.0-dev#117
Python version: 3.12.7
Operating system: posix
Command line: commix.py --url=*************************************************************** -p ******** 

Traceback (most recent call last):
  File \"commix.py", line 36, in <module>
    main()
  File \"commix.py", line 31, in main
    import src.core.main
  File \"main.py", line 902, in <module>
    main(filename, url, http_request_method)
  File \"main.py", line 560, in main
    controller.do_check(url, http_request_method, filename)
  File \"controller.py", line 743, in do_check
    perform_checks(url, http_request_method, filename)
  File \"controller.py", line 715, in perform_checks
    headers_checks(url, http_request_method, filename, timesec)
  File \"controller.py", line 650, in headers_checks
    http_headers_injection(url, http_request_method, filename, timesec)
  File \"controller.py", line 488, in http_headers_injection
    referer_injection(url, http_request_method, filename, timesec)
  File \"controller.py", line 459, in referer_injection
    if check_parameter != header_name or not injection_proccess(url, check_parameter, http_request_method, filename, timesec):
                                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File \"controller.py", line 364, in injection_proccess
    url = command_injection_heuristic_basic(url, http_request_method, check_parameter, the_type, header_name, inject_http_headers)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File \"controller.py", line 149, in command_injection_heuristic_basic
    response, url = heuristic_request(url, http_request_method, check_parameter, payload, whitespace)
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File \"controller.py", line 83, in heuristic_request
    payload, prefix = parameters.prefixes(payload, prefix="")
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File \"parameters.py", line 540, in prefixes
    specify_referer_parameter(parameter)
  File \"parameters.py", line 754, in specify_referer_parameter
    settings.TESTABLE_VALUE = checks.process_custom_injection_data(referer).replace(settings.ASTERISK_MARKER, settings.INJECT_TAG)
                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'replace'