A major security vulnerability has been discovered in the MySQL Server product of Oracle MySQL (Component: InnoDB). The affected versions include 8..32 and prior. This easily exploitable vulnerability enables a high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful exploitation of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete Denial of Service - DOS) of the MySQL Server. In this article, we will discuss the code snippets, original references, and exploit details related to CVE-2023-21911.

Code Snippet

The vulnerability lies in the InnoDB component of MySQL Server. The following code snippet is a brief example of where the vulnerability may exist:

InnoDB_struct {
    process_data(); // Vulnerable function containing the flaw

1. [Oracle Critical Patch Update Advisory - April 2023] (https://www.oracle.com/security-alerts/cpuapr2023.html)
2. [CVE-2023-21911 Detail] (https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-21911)
3. [National Vulnerability Database (NVD) - CVE-2023-21911] (https://nvd.nist.gov/vuln/detail/CVE-2023-21911)

Exploit Details

An attacker with high privileges (such as administrative access) and network access to the affected MySQL Server can exploit this vulnerability. The attacker can create and execute malicious SQL queries by manipulating the data structures in the InnoDB component leading to a hang or repeatedly crash the server. This result in a complete Denial of Service (DOS), making the MySQL Server unavailable to legitimate users.

CVSS 3.1 Base Score and Vector

CVE-2023-21911 has a CVSS 3.1 Base Score of 4.9, which signifies Availability impacts. The CVSS Vector for this vulnerability is (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).


To mitigate this vulnerability, it is highly recommended to apply the required security patches provided by Oracle as part of their Critical Patch Update (CPU) Advisory. Additionally, ensure that your MySQL Server has the latest updates and follows best security practices.


CVE-2023-21911 is a significant vulnerability in the MySQL Server product of Oracle MySQL, specifically affecting the InnoDB component. By exploiting this vulnerability, an attacker with high privileges and network access can compromise the server and cause a hang or repeatedly crash the server, leading to a complete Denial of Service (DOS). It is crucial to apply the necessary security patches and follow the best security practices to mitigate the risk associated with this vulnerability.


Published on: 04/18/2023 20:15:00 UTC
Last modified on: 04/27/2023 15:15:00 UTC