CVE-2024-21013

What it actually does

The vulnerability in the MySQL Server Optimizer component allows a high-privileged network attacker to trigger a denial of service by causing the server to hang or crash repeatedly.

Why it matters to the business

Successful exploitation can lead to unplanned database outages, disrupting applications and services reliant on the MySQL database, potentially causing operational downtime and data unavailability.

How an attack unfolds

An attacker with high privileges authenticates to the MySQL server and crafts specific queries or network packets that exploit weaknesses in the optimizer, leading to resource exhaustion or crash.

How to fix it

Upgrade MySQL Server to the latest supported versions that address the optimizer flaw beyond the affected releases.

How to confirm the fix worked

Confirm MySQL instances are running patched versions, review release notes for optimizer fixes, and validate stability under query loads in test environments.

Typical attack path

1. Obtain high-privileged credentials for the MySQL server
2. Establish network connection using supported protocols
3. Issue crafted queries designed to stress the optimizer logic
4. Trigger repeated hangs or crashes resulting in complete denial of service

How to detect it

Inspect MySQL error and crash logs for repeated optimizer-induced hangs, correlate with audit logs showing high-privileged network sessions, and watch for sudden spikes in resource usage tied to query processing.

What your security team should do

• Apply available patches to all MySQL Server instances promptly
• Limit network exposure and enforce least-privilege access controls
• Enable detailed logging and monitor for optimizer-related crashes
• Review and restrict high-privileged accounts with network access