A new critical vulnerability has been discovered in the MySQL Server product of Oracle MySQL, specifically affecting the partition component of the server. The vulnerability has been assigned the identifier CVE-2023-21953 and affects supported versions 8..32 and prior. This vulnerability allows a high privileged attacker with network access via multiple protocols to compromise the MySQL server. Successful exploitation of this vulnerability can lead to the unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of the MySQL server. It has a CVSS 3.1 base score of 4.9, indicating availability impacts, and the CVSS vector is (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).

Exploit Details

The vulnerability lies in the partition component, which is responsible for managing how data is organized and distributed across multiple tables in the database. Specifically, the vulnerability allows an attacker with high privileged access, like a database administrator or a user with similar privileges, to exploit MySQL server and potentially cause it to crash, hang or become utterly non-responsive, impacting the availability of the server.

The following code snippet demonstrates how an attacker could exploit this vulnerability

CREATE TABLE vulnerable_table (
    id INT,
    data VARCHAR(256)
) PARTITION BY RANGE (id) (
    PARTITION p VALUES LESS THAN (100),
    PARTITION p1 VALUES LESS_THAN (200)
);

-- Attacker sends specially crafted SQL query
SELECT * FROM vulnerable_table WHERE id = 'malicious_input';

The malicious_input value in the example above could be crafted in such a way that it triggers the vulnerability within the MySQL server partition component. As a result, the server could crash or hang, leading to a complete denial of service for any users attempting to access the affected database system.

- CVE Details
- Oracle MySQL Security Advisory

Mitigation Steps

To protect your MySQL server environment from this vulnerability, it is highly recommended to update your MySQL server version to the latest release, which contains the necessary fix for this issue. Oracle has provided patches to address this vulnerability in the latest software releases.

Administrators should also ensure that users with high privileged access are limited to a minimal number and that these accounts have strong, unique passwords to minimize the risk of unauthorized access.

In conclusion, CVE-2023-21953 poses a significant threat to the availability of MySQL server instances that run on affected versions, and it is crucial for administrators to apply patches and follow best practices to secure their environments. Failing to do so leaves systems vulnerable to attacks by high privileged users, who could potentially bring down critical database services in an organization or even cause data loss.

Timeline

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