CVE-2024-20976 in MySQL Server
Summary
by MITRE • 02/17/2024
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.35 and prior and 8.2.0 and prior. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. 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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Analysis
by VulDB Data Team • 05/08/2025
The vulnerability identified as CVE-2024-20976 resides within the MySQL Server optimizer component of Oracle MySQL database systems, representing a significant availability risk that affects multiple versions including 8.0.35 and earlier releases as well as 8.2.0 and prior iterations. This flaw operates at the core of MySQL's query execution engine where the optimizer component is responsible for determining the most efficient execution plan for database queries. The vulnerability's classification as easily exploitable indicates that attackers with high privileged network access can leverage this weakness to cause substantial disruption to database operations. The CVSS base score of 4.9 reflects the moderate severity of the availability impact, though the potential for complete denial of service makes this vulnerability particularly concerning for production environments where database availability is critical. The attack vector requires network access with high privileges, suggesting that the vulnerability is not easily exploitable by casual attackers but poses a real threat to systems where unauthorized privileged access might occur.
The technical nature of this vulnerability stems from improper handling within the server optimizer module, which is responsible for analyzing and executing database queries efficiently. When specific query patterns are processed through the affected MySQL versions, the optimizer encounters a condition that leads to either a complete hang or repeated crashes of the database server process. This behavior manifests as a denial of service condition where legitimate database operations cannot proceed due to the server becoming unresponsive or crashing repeatedly. The vulnerability's impact is particularly severe because the optimizer is a fundamental component that processes all database queries, meaning that any query execution can potentially trigger the flaw. The fact that this vulnerability affects multiple versions suggests a systemic issue within the query optimization logic that has persisted across different MySQL releases, indicating the flaw may be rooted in core algorithmic handling rather than a simple code oversight.
Operational impacts of CVE-2024-20976 extend beyond simple service disruption to potentially cause significant business interruptions in environments where MySQL databases serve as critical infrastructure components. Organizations relying on MySQL for transaction processing, application data storage, or enterprise information systems face the risk of complete service outages that can cascade across dependent applications and services. The vulnerability's ability to cause either a hang or frequent crashes creates an unpredictable operational environment where database administrators must constantly monitor and potentially restart database services. This type of availability impact aligns with CWE-400 which categorizes improper handling of resource consumption and system resource exhaustion scenarios, while also mapping to ATT&CK technique T1499.1 which involves network denial of service attacks targeting database systems. The vulnerability's exploitation requires high privilege access, suggesting that it may be leveraged by insider threats or attackers who have already compromised administrative credentials, making it particularly dangerous in environments where privileged access is not adequately controlled.
Mitigation strategies for CVE-2024-20976 should prioritize immediate patching of affected MySQL installations to the latest available versions that contain the fix for this optimizer vulnerability. Organizations should implement network segmentation and access controls to limit privileged network access to MySQL servers, reducing the attack surface available to potential exploiters. Database administrators should monitor for unusual patterns of query execution that might indicate exploitation attempts, particularly focusing on complex queries that might trigger the optimizer path. The implementation of robust monitoring solutions that can detect database server hangs or crashes can provide early warning of exploitation attempts. Additionally, organizations should consider implementing database activity monitoring tools that can identify potentially malicious query patterns and provide alerts when unusual database behavior occurs. Security teams should also review and enforce strict access control policies for database administrative accounts, ensuring that only authorized personnel have the necessary privileges to access database servers. The vulnerability's impact on availability makes it critical for organizations to maintain comprehensive backup and recovery procedures that can quickly restore database services in case of exploitation, while also implementing redundant database systems where possible to minimize service disruption during remediation efforts.