A new security vulnerability has been discovered which affects several versions of Oracle MySQL Server software. This article will discuss the details of this vulnerability, including affected versions, the vector of the attack, and the possible consequences if exploited. In addition, we will provide a relevant code snippet and links to the original references for those who wish to dive deeper into the issue.
The Vulnerability
This particular vulnerability has been assigned the Common Vulnerabilities and Exposures (CVE) identifier CVE-2025-21536. It affects the MySQL Server's Optimizer component, which is responsible for processing and optimizing SQL query execution. The affected Oracle MySQL Server versions are as follows:
9..1 and earlier
An attacker with high-level privileges and network access through multiple protocols can potentially exploit this vulnerability, resulting in unauthorized ability to cause a hardware hang or frequently repeatable crash of the MySQL Server. This in turn can lead to a complete Denial-of-Service (DOS) attack, significantly impacting the availability of the affected database server.
The vulnerability has been given a Common Vulnerability Scoring System (CVSS) 3.1 base score of 4.9, which reflects the potential impact on availability. The full 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.
Code Snippet
While no specific code snippet has been provided or has become publicly available that demonstrates the exploitation of this vulnerability, users might notice their MySQL Server instance unresponsive during the exploitation or a series of crashes in their system logs. Monitoring and logging tools can help administrators identify any unusual activity or repeated crashing.
Mitigation
To mitigate this vulnerability, you are advised to update your MySQL Server software to the latest available version, which should include security patches addressing this issue. You can find specific patch information for the affected versions through the MySQL Server Release Notes and the Oracle Critical Patch Update Advisory. You should also abide by the principle of least privilege, restricting user access and ensuring that only necessary users have high-level privileges.
For further details on this vulnerability, please consult the following resources
- NIST National Vulnerability Database (NVD) Entry: CVE-2025-21536
- Oracle Critical Patch Update Advisory - January 2025
- MySQL Server Releases and Release Notes
Conclusion
This article aims to provide an overview of the recently discovered CVE-2025-21536 vulnerability in Oracle MySQL Server's Optimizer component. By understanding the risks and taking appropriate precautions such as applying security patches and limiting high-level user access, administrators can protect their MySQL Server instances against potential exploitation attempts that could lead to a complete DOS attack.
Timeline
Published on: 01/21/2025 21:15:19 UTC
Last modified on: 01/22/2025 19:15:12 UTC