Home/CVE/Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are a
CVE

CVE-2026-21949

Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are a

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).

MEDIUM · CVSS 6.5 EPSS 0.00068
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-400Uncontrolled Resource Consumption
▤

Affected Products & Versions

1
oracle mysql server>= 9.0.0 and <= 9.5.0
▣

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · secalert_us@oracle.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD20 Jan 2026 · 10:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC triage · cisa-vulnrichment
Exploitation
none
Automatable
no
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
⚑

Vendor Advisories

1
oracle-cpuoracle-cpu-MySQL-Server-8478--CVE-2026-21949
🔗

References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://www.oracle.com/security-alerts/cpujan2026.htmlVendor Advisory
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