diff --git a/sigma/conversion/base.py b/sigma/conversion/base.py
index fd512e72..9adfe148 100644
--- a/sigma/conversion/base.py
+++ b/sigma/conversion/base.py
@@ -114,7 +114,7 @@ def convert_rule(self, rule : SigmaRule, output_format : Optional[str] = None) -
             # 2. Convert conditions
             error_state = "converting"
             states = [
-                ConversionState(processing_state=self.last_processing_pipeline.state)
+                ConversionState(processing_state=dict(self.last_processing_pipeline.state))
                 for _ in rule.detection.parsed_condition
             ]
             queries = [