---
id: "CVE-2026-101721"
kind: "vulnerability"
aliases: ["CVE-2026-101721"]
title: "MySQL Server: high-privilege user can crash the Components Services component"
severity: "medium"
cvss: 4.9
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["database", "mysql", "package", "self-hosted"]
not_affected_if: ["database-not-network-exposed", "version-outside-range"]
published_at: "2026-10-20T22:18:26+00:00"
first_seen_at: "2026-10-23T21:57:23+00:00"
updated_at: "2026-10-25T04:31:30+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-101721", "first_seen_at": "2026-10-23T21:57:23+00:00"}]
---

# MySQL Server: high-privilege user can crash the Components Services component

A flaw in the Server Components Services component of MySQL Server and MySQL Cluster lets a user with high privileges hang or repeatedly crash the server over the network. The sources describe only a denial of service, with no code execution or data exposure.

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

## How to check

- Run `SELECT VERSION();` on the MySQL server and compare against the affected ranges: 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, 26.7.0-26.7.1.

## Fix

- Move MySQL Server or MySQL Cluster to a release newer than the affected ranges above, using the vendor's patched build (the sources do not name the fixed version numbers).

## Timeline

- 2026-10-23T21:57:23+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-101721

## From the sources

Vulnerability in the MySQL Server, MySQL Cluster product of Oracle MySQL (component: Server: Components Services).  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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