Fix value lists within exception lists (#5963)

* Fix value lists within exception lists

detection_rules/exception.py

@@ -5,7 +5,7 @@
 """Rule exceptions data."""
 
 from collections import defaultdict
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 from datetime import UTC, datetime
 from pathlib import Path
 from typing import Any, get_args
@@ -72,7 +72,7 @@ class ExceptionItemEntry(BaseExceptionItemEntry, MarshmallowDataclassMixin):
         type: definitions.EsDataTypes
 
     operator: definitions.ExceptionEntryOperator
-    list_vals: ListObject | None = None
+    list_vals: ListObject | None = field(default=None, metadata={"data_key": "list"})
     value: str | None | list[str] = None
 
     @validates_schema

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "detection_rules"
-version = "1.6.26"
+version = "1.6.27"
 description = "Detection Rules is the home for rules used by Elastic Security. This repository is used for the development, maintenance, testing, validation, and release of rules for Elastic Security’s Detection Engine."
 readme = "README.md"
 requires-python = ">=3.12"