diff --git a/api/factories/file_factory.py b/api/factories/file_factory.py
index a5369a38d3..1c368a22ca 100644
--- a/api/factories/file_factory.py
+++ b/api/factories/file_factory.py
@@ -241,7 +241,11 @@ def _is_file_valid_with_config(
     ):
         return False
 
-    if config.allowed_file_extensions and file_extension not in config.allowed_file_extensions:
+    if (
+        input_file_type == FileType.CUSTOM
+        and config.allowed_file_extensions is not None
+        and file_extension not in config.allowed_file_extensions
+    ):
         return False
 
     if config.allowed_file_upload_methods and file_transfer_method not in config.allowed_file_upload_methods: