CVE-2021-2020: 
MySQL vulnerability analysis and mitigation

CVE-2021-2020 is a vulnerability in the MySQL Server product of Oracle MySQL, specifically affecting the Server Optimizer component. The vulnerability affects MySQL versions 8.0.20 and prior. This security flaw was disclosed in Oracle's January 2021 Critical Patch Update (Oracle CPU).

The vulnerability has a CVSS 3.1 Base Score of 6.5 (MEDIUM) with the vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. The vulnerability is easily exploitable by a low privileged attacker with network access via multiple protocols (NVD).

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

The vulnerability is considered easily exploitable by attackers with low privileges and network access. The attack requires no user interaction and can be conducted through multiple protocols (NVD).

The vulnerability has been patched in MySQL version 8.0.24 and later releases. Users are advised to upgrade to the fixed versions. For Fedora users, updates are available through the package manager for mysql-connector-odbc-8.0.23-1 and community-mysql-8.0.23-1 (Fedora Update, Fedora Update).