CVE-2025-30695: Oracle MySQL Server InnoDB DoS Vulnerability

CVE-2025-30695 Overview

CVE-2025-30695 is a vulnerability in the InnoDB component of Oracle MySQL Server. The flaw allows a high-privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful exploitation can cause a hang or frequently repeatable crash, resulting in a complete denial of service. The vulnerability also permits unauthorized update, insert, or delete access to some MySQL Server accessible data. Oracle addressed the issue in the April 2025 Critical Patch Update.

Critical Impact
Authenticated attackers can trigger a complete denial of service of MySQL Server and modify a subset of accessible data through the InnoDB storage engine.

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

Discovery Timeline

2025-04-15 - Oracle publishes the vulnerability in the April 2025 Critical Patch Update
2025-04-15 - CVE-2025-30695 published to the National Vulnerability Database
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-30695

Vulnerability Analysis

The vulnerability resides in the InnoDB storage engine of Oracle MySQL Server. InnoDB is the default transactional storage engine responsible for row-level locking, crash recovery, and ACID compliance. The flaw is classified under [CWE-284] Improper Access Control, indicating that the engine fails to properly restrict certain operations available to authenticated database users.

An authenticated attacker holding elevated database privileges can send crafted queries or protocol traffic that place InnoDB into an inconsistent state. The result is either a process hang or a frequently repeatable crash that terminates the MySQL Server. Beyond availability impact, the same interaction path allows the attacker to bypass expected restrictions and issue unauthorized UPDATE, INSERT, or DELETE statements against a subset of server-accessible data.

The attacker must already possess high privileges within the database, which limits mass exploitation but raises the risk from compromised administrative accounts, third-party integrations, and application service accounts that connect with excessive rights.

Root Cause

The root cause is improper access control within InnoDB when handling specific operations reachable over MySQL's network protocols. Access decisions are not enforced consistently, allowing privileged operations to trigger both integrity violations and instability in the storage engine. See the Oracle Security Alert April 2025 for vendor-confirmed technical scope.

Attack Vector

Exploitation requires network access to the MySQL Server and authenticated credentials with high privileges. Multiple MySQL protocols are viable delivery paths. No user interaction is required, and the attack complexity is low once valid credentials are held. Refer to the NetApp Security Advisory NTAP-20250502-0006 for platform-specific impact context.

Detection Methods for CVE-2025-30695

Indicators of Compromise

Unexpected MySQL Server crashes or hangs with InnoDB-related entries in the error log such as assertion failures or forced shutdowns.
Repeated abnormal disconnects from privileged accounts followed by service restarts.
Unexplained UPDATE, INSERT, or DELETE events in binlog or audit logs originating from administrative sessions.
Sudden spikes in InnoDB deadlock counters or long-running transactions preceding a crash.

Detection Strategies

Monitor MySQL error logs for InnoDB assertion messages, [ERROR] entries, and unexpected mysqld restarts.
Enable and review the MySQL Enterprise Audit plugin or general query log for anomalous statements issued by high-privileged accounts.
Correlate authentication events for administrative users with subsequent server instability windows.

Monitoring Recommendations

Track MySQL Server uptime and process restart frequency through infrastructure monitoring.
Alert on privileged account logins from unexpected source addresses or applications.
Baseline query patterns for service accounts and flag deviations that include DDL or bulk write operations against InnoDB tables.

How to Mitigate CVE-2025-30695

Immediate Actions Required

Apply the Oracle April 2025 Critical Patch Update to all affected MySQL Server 8.0, 8.4, and 9.x instances.
Inventory database accounts and remove or downgrade unnecessary high-privilege grants.
Restrict network exposure of MySQL Server to trusted application tiers and management networks only.
Rotate credentials for administrative and service accounts that connect to affected servers.

Patch Information

Oracle released fixes in the April 2025 Critical Patch Update. Upgrade MySQL Server to version 8.0.42, 8.4.5, or 9.3.0 or later as applicable. Full patch details are available in the Oracle Security Alert April 2025. NetApp customers should consult the NetApp Security Advisory NTAP-20250502-0006 for embedded product guidance.

Workarounds

Enforce least-privilege on all MySQL accounts and revoke administrative rights from application service accounts.
Place MySQL Server behind a firewall or private subnet and require VPN or bastion access for administration.
Enable MySQL audit logging and forward events to a centralized log platform for privileged-user monitoring.
Require TLS for client connections and disable unused MySQL protocols to reduce the exploitable surface.

bash

# Configuration example: restrict privileges and enforce network controls
REVOKE ALL PRIVILEGES ON *.* FROM 'app_user'@'%';
GRANT SELECT, INSERT, UPDATE, DELETE ON app_db.* TO 'app_user'@'10.0.%';
FLUSH PRIVILEGES;

# Bind MySQL to internal interface only
# /etc/mysql/mysql.conf.d/mysqld.cnf
bind-address = 10.0.0.10
require_secure_transport = ON