CVE-2025-30693: Oracle MySQL Cluster DoS Vulnerability

CVE-2025-30693 Overview

CVE-2025-30693 is a vulnerability in the MySQL Server product of Oracle MySQL affecting the InnoDB storage engine component. This easily exploitable vulnerability allows a high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful exploitation can result in an unauthorized ability to cause a hang or frequently repeatable crash (complete denial of service) of MySQL Server, as well as unauthorized update, insert, or delete access to some MySQL Server accessible data.

Critical Impact

High privileged attackers can cause complete denial of service through server crashes and perform unauthorized data modifications on MySQL Server deployments running affected versions.

Affected Products

• Oracle MySQL Server versions 8.0.0 through 8.0.41
• Oracle MySQL Server versions 8.4.0 through 8.4.4
• Oracle MySQL Server versions 9.0.0 through 9.2.0
• Oracle MySQL Cluster (corresponding versions)

Discovery Timeline

• April 15, 2025 - CVE-2025-30693 published to NVD
• November 3, 2025 - Last updated in NVD database

Technical Details for CVE-2025-30693

Vulnerability Analysis

This vulnerability resides in the InnoDB storage engine, which is the default and most commonly used storage engine in MySQL. The flaw is classified under CWE-284 (Improper Access Control), indicating that the vulnerability stems from inadequate access control mechanisms within the InnoDB component.

The vulnerability is network-exploitable and requires no user interaction, though it does require high privileges to execute. This means an attacker would need administrative or similarly elevated credentials to the MySQL server before exploitation is possible. Despite this requirement, the attack complexity is low, making it easily exploitable once the prerequisite access is obtained.

The impact primarily affects availability through denial of service conditions, with secondary impact on data integrity through unauthorized data modification capabilities.

Root Cause

The vulnerability is rooted in improper access control (CWE-284) within the InnoDB storage engine. The flaw allows authenticated users with high privileges to perform operations that can destabilize the database server or manipulate data beyond their intended authorization scope. The InnoDB component fails to properly validate or restrict certain operations, leading to potential crashes or unauthorized data modifications.

Attack Vector

The attack vector is network-based, allowing remote exploitation via multiple database protocols. An attacker with high privileges (such as a database administrator or user with elevated MySQL permissions) can leverage network connectivity to the MySQL server to trigger the vulnerability.

The exploitation does not require any user interaction and can be performed directly against the MySQL service. The attacker could craft specific database operations targeting the InnoDB component that would cause the server to hang or crash repeatedly, effectively creating a denial of service condition. Additionally, the attacker may gain the ability to modify data they should not have access to alter.

Since no verified code examples are available for this vulnerability, organizations should refer to the Oracle Critical Patch Update for detailed technical information about the vulnerability mechanics and exploitation patterns.

Detection Methods for CVE-2025-30693

Indicators of Compromise

• Unexpected MySQL server crashes or hangs, particularly those involving InnoDB operations
• Unusual data modification activity from high-privileged accounts
• Repeated server restarts or service interruptions without clear operational cause
• Anomalous network connections to MySQL services from unexpected sources

Detection Strategies

• Monitor MySQL error logs for InnoDB-related crashes, hangs, or unexpected terminations
• Implement database activity monitoring (DAM) to track privileged user operations and data modifications
• Review audit logs for unusual patterns of administrative commands targeting InnoDB tables
• Deploy intrusion detection systems (IDS) with signatures for MySQL exploitation attempts

Monitoring Recommendations

• Enable MySQL general query log and slow query log for forensic analysis
• Configure alerts for MySQL service restarts or high availability failover events
• Monitor privileged account activity with particular attention to data modification operations
• Track network connections to MySQL ports (3306) for anomalous patterns or sources

How to Mitigate CVE-2025-30693

Immediate Actions Required

• Apply the Oracle Critical Patch Update from April 2025 immediately
• Review and restrict high-privilege MySQL account access to only essential personnel
• Implement network segmentation to limit MySQL server exposure
• Enable comprehensive audit logging for privileged database operations

Patch Information

Oracle has released a security patch as part of the April 2025 Critical Patch Update. The patch addresses the improper access control issue in the InnoDB storage engine. Organizations should upgrade to the following patched versions:

• MySQL Server 8.0.42 or later for the 8.0.x branch
• MySQL Server 8.4.5 or later for the 8.4.x branch
• MySQL Server 9.2.1 or later for the 9.x branch

Additional security advisories have been issued by Debian LTS and NetApp for their respective distributions and products.

Workarounds

• Restrict network access to MySQL servers using firewall rules and network ACLs
• Implement the principle of least privilege for all MySQL accounts
• Consider deploying MySQL in private network segments not directly accessible from untrusted networks
• Enable MySQL Enterprise Firewall if available in your deployment to filter potentially malicious queries

# Configuration example - Restrict MySQL network binding and enforce TLS
# Add to my.cnf or my.ini configuration file

[mysqld]
# Bind only to specific internal interface
bind-address = 10.0.0.50

# Require encrypted connections
require_secure_transport = ON

# Enable audit logging for privileged operations
audit_log = FORCE_PLUS_PERMANENT
audit_log_policy = ALL