CVE-2020-2923: 
MySQL vulnerability analysis and mitigation

CVE-2020-2923 is a vulnerability in the MySQL Server product of Oracle MySQL, specifically affecting the Server Optimizer component. The vulnerability affects MySQL versions 8.0.19 and prior. This vulnerability was discovered in December 2019 and publicly disclosed in April 2020 (MITRE).

The vulnerability has been assigned a CVSS 3.0 Base Score of 4.9 (Medium severity) with the following vector: CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H. The vulnerability requires high privileges and network access via multiple protocols to exploit (NETAPP).

A successful exploitation of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server (MITRE).

The vulnerability is considered easily exploitable but requires high privileged attacker access with network connectivity. The attack complexity is rated as low, requiring no user interaction (NETAPP).

The vulnerability has been fixed in MySQL version 8.0.20. Users are advised to upgrade to this version or later. Ubuntu users can update to mysql-server-8.0 version 8.0.20-0ubuntu0.20.04.1 for Ubuntu 20.04 and version 8.0.20-0ubuntu0.19.10.1 for Ubuntu 19.10 (UBUNTU).