diff --git a/reactos/ntoskrnl/ex/mutant.c b/reactos/ntoskrnl/ex/mutant.c
index 3d1170992db..fb3dd1f660e 100644
--- a/reactos/ntoskrnl/ex/mutant.c
+++ b/reactos/ntoskrnl/ex/mutant.c
@@ -69,6 +69,7 @@ ExpInitializeMutantImplementation(VOID)
     ObjectTypeInitializer.PoolType = NonPagedPool;
     ObjectTypeInitializer.DeleteProcedure = ExpDeleteMutant;
     ObjectTypeInitializer.ValidAccessMask = MUTANT_ALL_ACCESS;
+    ObjectTypeInitializer.InvalidAttributes = OBJ_OPENLINK;
     Status = ObCreateObjectType(&Name, &ObjectTypeInitializer, NULL, &ExMutantObjectType);
     if (!NT_SUCCESS(Status)) return FALSE;
     return TRUE;