Check invalid pipeline keys

sigma/processing/pipeline.py

@@ -488,6 +488,24 @@ def _clear_pipeline(self):
     @classmethod
     def from_dict(cls, d: dict) -> "ProcessingPipeline":
         """Instantiate processing pipeline from a parsed processing item description."""
+
+        custom_keys = [
+            k
+            for k in d.keys()
+            if k
+            not in (
+                "vars",
+                "transformations",
+                "postprocessing",
+                "finalizers",
+                "priority",
+                "name",
+                "allowed_backends",
+            )
+        ]
+        if custom_keys:
+            raise SigmaConfigurationError(f"Unkown keys {custom_keys}")
+
         vars = d.get("vars", dict())  # default: no variables
 
         items = d.get("transformations", list())  # default: no transformation

tests/test_processing_pipeline.py

@@ -5,6 +5,7 @@
     ProcessingPipeline,
     ProcessingItem,
     QueryPostprocessingItem,
+    SigmaPipelineParsingError,
 )
 from sigma.processing.transformations import transformations
 from sigma.processing.conditions import (
@@ -605,6 +606,35 @@ def test_processingpipeline_fromyaml(
     )
 
 
+def test_processingpipeline_fromyaml_invalid(
+    processing_item_dict, processing_item, postprocessing_item, processing_pipeline_vars
+):
+    with pytest.raises(
+        SigmaPipelineParsingError, match="Error in parsing of a Sigma processing pipeline"
+    ):
+        ProcessingPipeline.from_yaml(
+            """
+                {not a yaml
+            """
+        )
+
+
+def test_processingpipeline_fromyaml_unknown(
+    processing_item_dict, processing_item, postprocessing_item, processing_pipeline_vars
+):
+    with pytest.raises(SigmaConfigurationError, match="Unkown keys \['transformation'\]"):
+        ProcessingPipeline.from_yaml(
+            """
+        name: unknown
+        priority: 10
+        transformation:
+        - id: test
+          type: test
+          method: test
+            """
+        )
+
+
 def test_processingpipeline_fromdict_error(processing_item_dict_with_error):
     with pytest.raises(SigmaConfigurationError, match="Error in processing rule 1:.*2"):
         ProcessingPipeline.from_dict(