CVE-2024-21137 in MySQL Server
Summary
by MITRE • 07/17/2024
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).
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 10/18/2024
The vulnerability identified as CVE-2024-21137 represents a critical availability issue within Oracle MySQL Server's optimizer component, affecting versions 8.0.35 and earlier, as well as 8.2.0 and earlier releases. This weakness resides in the server's query optimization logic, which forms a fundamental part of database operations and performance management. The vulnerability's classification as easily exploitable indicates that attackers with high privileges and network access can leverage this flaw to disrupt MySQL server operations. The attack vector operates through multiple network protocols, making it particularly concerning for environments where database servers are accessible over various communication channels. The CVSS base score of 4.9 reflects the significant availability impact, with a high privilege requirement and low attack complexity, suggesting that this vulnerability targets scenarios where attackers already possess elevated access levels within the network infrastructure.
The technical flaw manifests within the MySQL Server's optimizer subsystem, which is responsible for determining the most efficient execution plan for database queries. When specific query patterns or conditions are processed through this component, the optimizer fails to handle certain edge cases properly, leading to system instability. This malfunction results in complete denial of service conditions where the MySQL server becomes unresponsive or enters a continuous crash loop. The vulnerability's design allows for repeated exploitation, meaning that once the initial crash occurs, subsequent attempts can reliably reproduce the same failure state. The system's inability to maintain stable operation under these circumstances creates a persistent availability threat that can severely impact database-driven applications and services relying on MySQL for data storage and retrieval operations.
The operational impact of this vulnerability extends beyond simple service disruption to encompass broader business continuity concerns for organizations using affected MySQL versions. When a MySQL server experiences frequent crashes or hangs, it creates cascading effects throughout dependent applications, potentially leading to data access failures, transaction rollbacks, and complete service outages. The high privilege requirement suggests that this vulnerability is most likely exploited by attackers who have already gained administrative access to the network or database environment, making it particularly dangerous in scenarios where privilege escalation has occurred. Organizations may face extended downtime periods while investigating and resolving the instability, potentially resulting in significant financial losses and reputational damage. The vulnerability's presence in multiple version streams indicates that the underlying optimization logic contains fundamental flaws that require comprehensive patching or mitigation strategies across affected deployments.
Mitigation strategies for CVE-2024-21137 should prioritize immediate patch deployment from Oracle, as this represents the most effective solution to address the root cause of the optimizer failure. Organizations should also implement network segmentation and access controls to limit the attack surface, particularly reducing the exposure of MySQL servers to unnecessary network protocols and connections. Monitoring solutions should be enhanced to detect unusual server behavior patterns that might indicate exploitation attempts, including tracking connection failures, process crashes, and performance degradation metrics. The vulnerability's classification under CWE-121 (Buffer Copy without Checking Size of Input) and its mapping to ATT&CK technique T1499.004 (Endpoint Denial of Service) highlight the need for comprehensive security measures that address both the specific vulnerability and broader denial of service attack patterns. Additionally, implementing database connection pooling, query timeouts, and failover mechanisms can help reduce the impact of potential exploitation by providing alternative service paths and automatic recovery capabilities when primary database connections become unstable.