CVE-2026-21949 Details
Description
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 9.0.0-9.5.0. Easily exploitable vulnerability allows low 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 hang or frequently repeatable crash (complete DOS) of MySQL Server. 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 denial-of-service vulnerability has been identified in the Oracle MySQL Server product, specifically within the Optimizer component. This issue affects MySQL Server versions 9.0.0 through 9.5.0. The vulnerability is easily exploitable, allowing a low-privileged attacker with network access via multiple protocols to disrupt MySQL Server operations. Successful exploitation can lead to unauthorized actions causing the server to hang or crash frequently, resulting in a complete denial-of-service condition.
Metrics
CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Jan 21, 2026References to Advisories, Solutions, and Tools
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| URL | Source(s) | Tag(s) |
|---|---|---|
| https://www.oracle.com/security-alerts/cpujan2026.html | [email protected] | Vendor Advisory |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-400 | Uncontrolled Resource Consumption | CISA-ADP |
Affected Products
| Product | Versions |
|---|---|
| oracle mysql server | >= 9.0.0, <= 9.5.0 |
CPE
Remediation
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Change History
5 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| Jan 29, 2026 | Initial Analysis | [email protected] |
| Jan 21, 2026 | CVE Modified | CISA-ADP |
| Jan 20, 2026 | New CVE Received | [email protected] |