CVE-2023-21940 - Vulnerability in MySQL Server 8..32 and Prior Affecting Components Services and Allowing DOS Attacks

Overview:

A new vulnerability (CVE-2023-21940) has been discovered in the MySQL Server product of Oracle MySQL, specifically in the Server: Components Services component. This vulnerability affects supported versions 8..32 and prior. It is a difficult-to-exploit vulnerability that allows a high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of the MySQL Server. The CVSS 3.1 Base Score for this vulnerability is 4.4 with Availability impacts. The CVSS Vector is (CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H).

Original References

- CVE Details: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-21940
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-21940

Exploit Details

As mentioned earlier, the attacker needs to have high privileges with network access via multiple protocols in order to exploit this vulnerability. The attack can cause a hang or frequently repeatable crash, resulting in a complete DOS (Denial of Service) of the MySQL Server.

Here's a code snippet, showcasing how the attack might be executed

import socket

TARGET_IP = "192.168.1.100"   # Replace with the IP address of the target MySQL Server
TARGET_PORT = 3306            # Default MySQL port

def crash_mysql_server():
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.connect((TARGET_IP, TARGET_PORT))
    
    # Craft the malicious payload here and send it to the server
    
    sock.close()

if __name__ == "__main__":
    crash_mysql_server()

Please note that this code snippet is for educational purposes only and should not be used to undertake any malicious activities.

Mitigation

Oracle has released patches to address this vulnerability. It is highly recommended to update your MySQL Server to the latest version (above 8..32) to protect against this vulnerability. In addition, it's a good practice to restrict access to the MySQL Server only to trusted users and limit the number of high privileged users in your system.

Conclusion

The vulnerability CVE-2023-21940 in MySQL Server's Components Services can lead to complete DOS of the server, rendering it unusable. It is essential to update your MySQL Server to the latest version and adhere to best practices for user privileges and network access controls to reduce the likelihood of a successful attack. Stay informed about new vulnerabilities and patches by monitoring resources like CVE Details, NVD, and vendor announcements.

Timeline

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