Vulnerability in the MySQL Server, MySQL Cluster product of Oracle MySQL (component: Server: Pluggable Auth). Supported versions that are affected are MySQL Server: 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1; MySQL Cluster: 8.0.0-8.0.49, 8.4.0-8.4.12, 9.7.0-9.7.3 and 26.7.0-26.7.1. Easily exploitable vulnerability allows low privileged attacker with network access via multiple protocols to compromise MySQL Server, MySQL Cluster. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server, MySQL Cluster. CVSS 3.1 Base Score 6.5 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H).

A flaw was found in MySQL's Pluggable Auth component. An authenticated remote attacker with low privileges can exploit this vulnerability over the network across multiple protocols. Successful exploitation allows the attacker to cause the database service to hang or repeatedly crash, resulting in a Denial of Service (DoS).

This vulnerability is rated Moderate because exploitation requires valid authentication credentials with low privileges, limiting the attack surface to authenticated users, and the resulting impact is confined to service availability without compromising confidentiality or data integrity. In standard Red Hat enterprise environments, MySQL deployments are typically isolated within internal network segments and restricted to authorized application tiers. Consequently, exposure is limited to configurations where untrusted entities possess active database credentials. Red Hat Enterprise Linux 10 Affected mysql8.4 Red Hat Enterprise Linux 6 Not affected mysql Red Hat Enterprise Linux 9 Affected mysql Red Hat Hardened Images Not affected mariadb10.11 Red Hat Hardened Images Not affected mariadb11.8 https://www.cve.org/CVERecord?id=CVE-2026-101728 https://nvd.nist.gov/vuln/detail/CVE-2026-101728 https://www.oracle.com/security-alerts/cpuoct2026.html