Description
Vulnerability in the MySQL Server, MySQL Cluster product of Oracle MySQL (component: Server: Replication). 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. Difficult to exploit 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 4.4 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H).
Published: 2026-10-20
Score: 4.4 Medium
EPSS: < 1% Very Low
KEV: No
Impact: Denial of Service (complete crash)
Action: Patch Urgently
AI Analysis

Impact

The vulnerability is located in the replication component of Oracle MySQL Server and MySQL Cluster. An attacker who can reach the database over the network and has high privileges can trigger the defect. When the defect is exploited, the server or cluster instance can hang or crash repeatedly, making the database unavailable. The flaw does not expose data or provide privilege escalation; it solely impacts the availability of the service. The CVSS 3.1 Base Score of 4.4 indicates that the primary effect is downtime rather than confidentiality or integrity loss.

Affected Systems

Affected systems include Oracle 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, as well as Oracle 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. These versions are vulnerable to the replication‑related defect described.

Risk and Exploitability

The CVSS vector (AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H) shows that the attacker needs network access and high privileges. The description states exploitation is difficult and no public exploit is known. EPSS score is < 1%, indicating a very low but non‑zero exploitation probability. The potential for a full service crash imposes a moderate risk. The vulnerability is not listed in CISA KEV, indicating no widespread exploit activity yet, yet any organization operating the affected versions should apply the vendor patch as soon as it is released.

Generated by OpenCVE AI on October 23, 2026 at 05:27 UTC.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Apply the latest Oracle MySQL patch that addresses this replication issue or upgrade to a version newer than 8.4.12 for Server and 8.0.49 for Cluster.
  • Restrict external access to the MySQL service to trusted IP addresses or networks, limiting the attack surface for network‑based exploitation.
  • If replication is not required for a given deployment, disable it or remove unused replication features to reduce the potential impact of the defect.

Generated by OpenCVE AI on October 23, 2026 at 05:27 UTC.

Tracking

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Advisories

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History

Fri, 23 Oct 2026 02:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-770

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

Type Values Removed Values Added
Title Denial of Service via Replication Fault in Oracle MySQL Server and Cluster mysql: mysql: Denial of service in replication component
References
Metrics threat_severity

None

 threat_severity

Moderate

Thu, 22 Oct 2026 18:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-284
Metrics ssvc

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

Wed, 21 Oct 2026 02:00:00 +0000

Type Values Removed Values Added
Title Denial of Service via Replication Fault in Oracle MySQL Server and Cluster
Weaknesses CWE-400
CWE-770

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: Replication). 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. Difficult to exploit 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 4.4 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/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': 4.4, 'vector': 'CVSS:3.1/AV:N/AC:H/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: 2026-10-22T17:31:20.788Z

Reserved: 2026-09-28T15:40:09.505Z

Link: CVE-2026-101766

cve-icon Vulnrichment

Updated: 2026-10-22T17:26:32.362Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-20T22:18:31.947

Modified: 2026-10-22T18:17:21.150

Link: CVE-2026-101766

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-10-20T21:22:48Z

Links: CVE-2026-101766 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-10-23T05:30:03Z

Weaknesses
  • CWE-284

    Improper Access Control

  • CWE-400

    Uncontrolled Resource Consumption