CVE-2024-21142

What it actually does

High-privileged network attacker can abuse the Server: Security: Privileges component to trigger a hang or repeatable crash, resulting in complete denial of service for the MySQL Server process.

Why it matters to the business

Successful exploitation causes unplanned database downtime, interrupting dependent applications, transactions, and services until the server is restarted or recovered.

How an attack unfolds

An attacker with high-privileged credentials connects to MySQL over supported network protocols and issues specially crafted requests that exploit the privileges handling flaw, forcing the server into a hung or crashed state without requiring further authentication bypass.

How to fix it

Upgrade affected MySQL 8.0 installations to versions later than 8.0.37 and MySQL 8.4 installations to versions later than 8.4.0. Restrict network access to privileged accounts and apply least-privilege principles until patches are deployed.

How to confirm the fix worked

Confirm MySQL version is no longer in the affected range, review server error logs for absence of privilege-related crash signatures after upgrade, and perform controlled privilege operation tests to verify stability.

Typical attack path

1. Obtain or compromise high-privileged MySQL credentials
2. Establish network connection using one of the supported protocols
3. Issue targeted requests against the privileges component
4. Induce server hang or crash resulting in DoS

How to detect it

Review MySQL error and general query logs for sudden server crashes or hangs preceded by connections from privileged accounts; correlate with authentication events and look for repeated failed or abnormal privilege-related operations around crash timestamps.

What your security team should do

• Apply vendor patches to all MySQL 8.0 and 8.4 instances immediately
• Audit and reduce the number of high-privileged network-accessible accounts
• Enforce network segmentation and firewall rules limiting MySQL exposure
• Enable enhanced logging for privileged sessions and monitor for anomalous query patterns