CVE-2024-21142 is a vulnerability in Oracle MySQL Server affecting versions 8.0.37 and earlier, as well as 8.4.0 and earlier. It resides in the server's privilege management component and allows a high-privileged attacker with network access to cause the server to hang or crash repeatedly, resulting in a complete denial-of-service (DoS) condition. The vulnerability can be exploited over multiple network protocols, increasing the attack surface. The CVSS 3.1 base score is 4.9, reflecting a medium severity primarily due to its impact on availability (no confidentiality or integrity impact). The attack requires the attacker to have high privileges on the MySQL Server, but no user interaction is needed. The underlying weakness is related to resource exhaustion (CWE-400), which suggests that the attacker can trigger conditions that consume excessive resources, leading to service disruption. No patches or exploits are currently publicly available, but the vulnerability is officially published and should be addressed promptly. This vulnerability does not allow data theft or modification but can disrupt services relying on MySQL, potentially affecting business continuity.

For European organizations, the primary impact of CVE-2024-21142 is service disruption due to denial-of-service attacks on MySQL Server instances. Organizations that use MySQL for critical applications, databases, or backend services may experience outages or degraded performance, affecting availability of services to customers and internal users. This can lead to operational downtime, loss of productivity, and potential financial losses. Since the vulnerability requires high privileges, the risk is elevated in environments where attackers have already gained elevated access, such as through insider threats or lateral movement after initial compromise. Industries with high reliance on database availability, such as finance, healthcare, e-commerce, and public sector services, are particularly vulnerable. Additionally, cloud service providers and managed service providers hosting MySQL databases in Europe could face cascading impacts if exploited. The lack of known exploits reduces immediate risk, but the ease of exploitation over network protocols means that once exploited, the impact can be widespread and disruptive.

European organizations should implement the following specific mitigations: 1) Monitor and restrict high-privilege access to MySQL Server instances, ensuring the principle of least privilege is enforced. 2) Apply network segmentation and firewall rules to limit network access to MySQL servers only to trusted hosts and services. 3) Deploy intrusion detection and prevention systems (IDS/IPS) to detect unusual patterns indicative of resource exhaustion or DoS attempts targeting MySQL. 4) Regularly audit MySQL user privileges and remove unnecessary high-privilege accounts. 5) Prepare for patch deployment by tracking Oracle's security advisories and applying updates promptly once patches are released. 6) Implement resource limits and connection throttling on MySQL servers to mitigate potential resource exhaustion attacks. 7) Maintain robust backup and recovery procedures to minimize downtime impact. 8) Conduct penetration testing and vulnerability assessments focused on privilege escalation and DoS scenarios in MySQL environments. These steps go beyond generic advice by focusing on privilege management, network controls, and proactive monitoring tailored to this vulnerability's characteristics.