CVE-2025-30696 is a vulnerability identified in Oracle MySQL Server affecting multiple supported versions: 8.0.0 to 8.0.41, 8.4.0 to 8.4.4, and 9.0.0 to 9.2.0. The flaw arises from improper access control mechanisms (CWE-284) within the server component, allowing a high privileged attacker with network access via multiple protocols to cause the server to hang or crash repeatedly, resulting in a complete denial of service (DoS). The vulnerability has a CVSS 3.1 base score of 4.9, indicating medium severity, with an attack vector of network (AV:N), low attack complexity (AC:L), requiring high privileges (PR:H), no user interaction (UI:N), unchanged scope (S:U), and impacting availability only (A:H). The attacker must already have high privileges on the MySQL server, which limits the attack surface but still poses a significant risk in multi-tenant or shared environments. The vulnerability does not affect confidentiality or integrity, but the availability impact can disrupt database services, potentially affecting dependent applications and business operations. No public exploits have been reported yet, but the vulnerability is easily exploitable given the low complexity and network accessibility. The lack of patches at the time of reporting necessitates immediate attention to access controls and monitoring. The vulnerability affects multiple protocols used by MySQL, broadening the potential attack vectors. This issue underscores the importance of strict privilege management and network segmentation for database servers.

For European organizations, the primary impact of CVE-2025-30696 is the potential for denial of service against MySQL database servers, which can disrupt critical business applications, e-commerce platforms, and internal services relying on MySQL. Organizations in sectors such as finance, healthcare, telecommunications, and government that use MySQL extensively could face operational downtime, leading to financial losses and reputational damage. The requirement for high privileges reduces the risk of external attackers exploiting this vulnerability directly; however, insider threats or attackers who have already compromised privileged accounts could leverage this flaw to cause service outages. The availability impact may also affect cloud service providers and managed service providers hosting MySQL instances for European clients, potentially cascading to multiple customers. Given the widespread use of MySQL in Europe, especially in small and medium enterprises and public sector organizations, the vulnerability poses a moderate but tangible risk to service continuity. Additionally, disruption of MySQL services could hinder compliance with data availability requirements under regulations like GDPR if service outages impact data access or processing.

1. Immediately review and restrict high privilege accounts on MySQL servers to the minimum necessary, ensuring that only trusted administrators have such access. 2. Implement strict network segmentation and firewall rules to limit network access to MySQL servers only to authorized hosts and management networks. 3. Monitor MySQL server logs and network traffic for unusual activity or repeated connection attempts that could indicate exploitation attempts. 4. Apply any available patches or updates from Oracle as soon as they are released for the affected MySQL versions. 5. Consider upgrading to newer MySQL versions beyond 9.2.0 if they are confirmed not vulnerable. 6. Use intrusion detection/prevention systems (IDS/IPS) tuned to detect anomalous MySQL traffic patterns. 7. Employ database activity monitoring solutions to detect abnormal commands or crashes. 8. Regularly back up MySQL databases to enable rapid recovery in case of service disruption. 9. Conduct internal audits of privilege assignments and network configurations to ensure compliance with least privilege and zero trust principles. 10. Educate administrators about the vulnerability and the importance of safeguarding privileged credentials.