Oracle MySQL Server up to 9.5.0 Pluggable Auth denial of service

Summaryinfo

A vulnerability marked as problematic has been reported in Oracle MySQL Server up to 9.5.0. This impacts an unknown function of the component Pluggable Auth. Performing a manipulation results in denial of service. This vulnerability is reported as CVE-2026-21965. The attack is possible to be carried out remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Oracle MySQL Server up to 9.5.0. It has been classified as problematic. This affects an unknown code of the component Pluggable Auth. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. The summary by CVE is:

Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Pluggable Auth). Supported versions that are affected are 9.0.0-9.5.0. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a partial denial of service (partial DOS) of MySQL Server. CVSS 3.1 Base Score 2.7 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L).

It is possible to read the advisory at oracle.com. This vulnerability is uniquely identified as CVE-2026-21965 since 01/05/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Additional levels of successful authentication are required for exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 297682 (Linux Distros Unpatched Vulnerability : CVE-2026-21965), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (297682), EUVD (EUVD-2026-3547) and CERT Bund (WID-SEC-2026-0168). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Red Hat Enterprise Linux
• Ubuntu Linux
• Oracle Linux
• RESF Rocky Linux
• Oracle MySQL

Productinfo

Type

• Database Software

Vendor

• Oracle

Name

• MySQL Server

Version

• 9.0
• 9.1
• 9.2
• 9.3
• 9.4
• 9.5.0

License

• open-source

Website

• Vendor: https://www.oracle.com

CPE 2.3info

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Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

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