Description
Vulnerability in the MySQL Server, MySQL Cluster product of Oracle MySQL (component: Server: Optimizer). 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 high 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 4.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).
Published: 2026-10-20
Score: 4.9 Medium
EPSS: < 1% Very Low
KEV: No
Impact: Denial of Service
Action: Patch Now
AI Analysis

Impact

The vulnerability in MySQL Server and MySQL Cluster’s Optimizer component allows a high‑privileged attacker with network access through multiple protocols to trigger a crash, leading to a complete denial of service. The flaw is a form of Resource Consumption (CWE‑400) and an Infinite Loop (CWE‑835) that can cause the database engine to hang or repeatedly crash, disrupting availability. The CVSS score of 4.9 (AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H) reflects moderate severity with network reachability, low attack complexity, and high privilege requirement, but no user interaction needed.

Affected Systems

Oracle MySQL Server and MySQL Cluster are affected. For MySQL Server, versions 8.4.0 through 8.4.12, 9.7.0 through 9.7.3, and 26.7.0 through 26.7.1 are vulnerable. For MySQL Cluster, versions 8.0.0 through 8.0.49, 8.4.0 through 8.4.12, 9.7.0 through 9.7.3, and 26.7.0 through 26.7.1 must be inspected.

Risk and Exploitability

The vulnerability requires an attacker to possess high privileges and network connectivity; these requirements are explicitly stated in the advisory. The assertion that the exploit is "moderately easy to exploit" is inferred from the description that an attacker with sufficient credentials can trigger the crash. The EPSS score of less than 1% indicates a very low probability of attack, and it is not listed in CISA’s KEV, indicating it has not yet been reported as a widely used exploit. The potential for an attacker to bring servers to a crash state makes the vulnerability a reliability risk for production databases, so security teams should monitor for abnormal query patterns and plan for swift recovery.

Generated by OpenCVE AI on November 5, 2026 at 19:44 UTC.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Apply the Oracle MySQL patch released in the October 2026 CPU to all affected MySQL Server and MySQL Cluster installations.
  • Restrict MySQL network exposure by limiting connections to the database to only required internal IP addresses and disabling unnecessary protocols.
  • Enable logging and monitoring of database crash events, and maintain recent backups to restore quickly in the event of a denial‑of‑service incident.

Generated by OpenCVE AI on November 5, 2026 at 19:44 UTC.

Tracking

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Advisories

No advisories yet.

History

Thu, 05 Nov 2026 17:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-400
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Fri, 23 Oct 2026 05:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-400

Fri, 23 Oct 2026 00:45:00 +0000

Type Values Removed Values Added
Title Denial of Service Vulnerability in MySQL Server and Cluster due to Optimizer Bug mysql: mysql: Denial of Service in Server Optimizer
Weaknesses CWE-835
References
Metrics threat_severity

None

 threat_severity

Moderate

Wed, 21 Oct 2026 01:00:00 +0000

Type Values Removed Values Added
Title Denial of Service Vulnerability in MySQL Server and Cluster due to Optimizer Bug
Weaknesses CWE-400

Tue, 20 Oct 2026 21:30:00 +0000

Type Values Removed Values Added
Description Vulnerability in the MySQL Server, MySQL Cluster product of Oracle MySQL (component: Server: Optimizer). 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 high 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 4.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).
First Time appeared Oracle
Oracle mysql Cluster
Oracle mysql Server
CPEs cpe:2.3:a:oracle:mysql_cluster:*:*:*:*:*:*:*:*
cpe:2.3:a:oracle:mysql_server:*:*:*:*:*:*:*:*
Vendors & Products Oracle
Oracle mysql Cluster
Oracle mysql Server
References
Metrics cvssV3_1

{'score': 4.9, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H'}

Subscriptions

Oracle Mysql Cluster Mysql Server
cve-icon MITRE

Status: PUBLISHED

Assigner: oracle

Published:

Updated: 2026-11-05T16:07:15.373Z

Reserved: 2026-09-28T15:40:09.494Z

Link: CVE-2026-101607

cve-icon Vulnrichment

Updated: 2026-11-05T16:02:01.075Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-20T22:18:14.430

Modified: 2026-11-05T17:17:30.550

Link: CVE-2026-101607

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-10-20T21:21:51Z

Links: CVE-2026-101607 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-11-05T19:45:15Z

Weaknesses
  • CWE-400

    Uncontrolled Resource Consumption

  • CWE-835

    Loop with Unreachable Exit Condition ('Infinite Loop')