CVE-2020-14845: 
MySQL vulnerability analysis and mitigation

CVE-2020-14845 is a vulnerability discovered in the MySQL Server product of Oracle MySQL, specifically affecting the Server Optimizer component. The vulnerability affects MySQL versions 8.0.21 and prior. This security issue was disclosed on October 21, 2020, as part of Oracle's Critical Patch Update (Oracle CPU).

The vulnerability has been assigned a CVSS 3.1 Base Score of 4.9 (Medium severity) with the following vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H. The vulnerability is considered easily exploitable and requires high privileged access with network accessibility via multiple protocols to compromise MySQL Server (MITRE CVE).

Successful exploitation of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash, leading to a complete Denial of Service (DoS) of MySQL Server. The vulnerability only affects availability, with no impact on confidentiality or integrity (NVD).

The vulnerability is considered easily exploitable but requires high privileged access. An attacker needs network access via multiple protocols to successfully exploit this vulnerability. No known exploits specifically targeting this vulnerability have been reported in the wild (Oracle CPU).

Oracle has released patches to address this vulnerability in MySQL version 8.0.22. Ubuntu users can update to mysql-server-8.0 version 8.0.22-0ubuntu0.20.10.2 for Ubuntu 20.10 and version 8.0.22-0ubuntu0.20.04.2 for Ubuntu 20.04 LTS (Ubuntu Notice).