diff --git a/core/detection/som_engine.py b/core/detection/som_engine.py
index 5aab8eaf7..683be768a 100644
--- a/core/detection/som_engine.py
+++ b/core/detection/som_engine.py
@@ -300,7 +300,7 @@ _shared_engine: Optional[SomEngine] = None
 _shared_lock = __import__("threading").Lock()
 
 
-def get_shared_engine(device: str = "cuda") -> Optional[SomEngine]:
+def get_shared_engine(device: str = "cpu") -> Optional[SomEngine]:
     """Singleton SomEngine partagé entre tous les modules."""
     global _shared_engine
     if _shared_engine is None: