---
id: "CVE-2026-101751"
kind: "vulnerability"
aliases: ["CVE-2026-101751"]
title: "MySQL Server: Group Replication flaw lets a privileged user crash the server"
severity: "medium"
cvss: 4.9
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["group-replication", "mysql", "package", "self-hosted"]
not_affected_if: ["auth-required", "managed-hosting", "standalone-server"]
published_at: "2026-10-20T22:18:30+00:00"
first_seen_at: "2026-10-23T21:57:23+00:00"
updated_at: "2026-10-25T04:31:21+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-101751", "first_seen_at": "2026-10-23T21:57:23+00:00"}]
---

# MySQL Server: Group Replication flaw lets a privileged user crash the server

A flaw in the Group Replication GCS component of MySQL Server and MySQL Cluster lets a highly privileged attacker over the network hang or repeatedly crash the database. The sources describe only availability impact, with no data read or code execution.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `SELECT @@version;` in MySQL to see whether the version is in an affected range (8.4.0 to 8.4.12, 9.7.0 to 9.7.3, 26.7.0 to 26.7.1, or MySQL Cluster 8.0.0 to 8.0.49).
- Check whether Group Replication is enabled with `SELECT * FROM performance_schema.replication_group_members;`

## Fix

- Upgrade MySQL Server to a release after the affected ranges listed by Oracle (the sources do not name the fixed version).
- Upgrade MySQL Cluster 8.0 to a release after 8.0.49 and 8.4 to a release after 8.4.12.

## Timeline

- 2026-10-23T21:57:23+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-101751

## From the sources

Vulnerability in the MySQL Server, MySQL Cluster product of Oracle MySQL (component: Server: Group Replication GCS).  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).

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_