A new vulnerability, identified as CVE-2023-21919, has been discovered in the MySQL Server product of Oracle MySQL, specifically in the Server: DDL component. This vulnerability affects supported versions 8..32 and prior. This post aims to provide an in-depth look at this easily exploitable vulnerability, including its potential impact, exploit details, and code snippets. We will also provide original references and solutions to protect your MySQL Server against such attacks.
Exploit Details
CVE-2023-21919 is a critical vulnerability that allows a high privileged attacker with network access via multiple protocols to compromise the MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (a complete DOS or Denial of Service) of the MySQL Server. The CVSS 3.1 Base Score for this vulnerability is 4.9 with Availability impacts. The CVSS Vector is as follows: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).
The vulnerability stems from the Server: DDL component, which is responsible for managing database schema objects, such as tables and views. It allows a high privileged attacker to cause MySQL Server to crash or hang, effectively making it unavailable to users.
Code Snippet
While there is no specific code snippet available that demonstrates the exploit at this time, such an attack could involve sending crafted SQL queries targeting the vulnerable DDL component. The exploit would likely involve the attacker leveraging their high privileges to trigger the vulnerability and cause a hang or crash of the MySQL Server instance.
For more information on this vulnerability, you can refer to the following original references
1. Oracle Critical Patch Update Advisory - January 2023 (Oracle): https://www.oracle.com/security-alerts/cpujan2023.html
2. CVE-2023-21919 Detail (National Vulnerability Database): https://nvd.nist.gov/vuln/detail/CVE-2023-21919
Mitigation
To mitigate the vulnerability, it is recommended to update your MySQL Server to the latest supported version (8..33 or higher). This update should contain the necessary patches to address the vulnerability. Please follow Oracle's official instructions for updating your MySQL Server installation:
1. MySQL Server 8..33 Update (Oracle): https://www.oracle.com/mysql/mysql-server-8..33-update/
Additionally, you should ensure that your MySQL Server follows industry-best security practices, such as:
Conclusion
CVE-2023-21919 is a critical vulnerability in the MySQL Server DDL component, which affects version 8..32 and prior. Successful exploitation can lead to a complete denial of service by crashing or hanging the MySQL Server instance. To protect your MySQL Server, it is essential to update your installation to the latest supported version and follow industry-best security practices.
Timeline
Published on: 04/18/2023 20:15:00 UTC
Last modified on: 04/27/2023 15:15:00 UTC