diff --git a/src/blackboard/operations.py b/src/blackboard/operations.py
index 7c1b8c0..d52c013 100644
--- a/src/blackboard/operations.py
+++ b/src/blackboard/operations.py
@@ -782,6 +782,11 @@ class Blackboard:
                 return {"error": "Task not found"}
 
             task_status = task_row["status"]
+            # BUG-32: 安全校验 — task 必须处于 waiting_human 才能推进
+            if task_status != "waiting_human":
+                conn.commit()
+                return {"error": f"Task is {task_status}, expected waiting_human"}
+
             if action == "approve":
                 if cp_type == "verify":
                     new_task_status = "done"