CVE-2023-21962 in MySQL Server
Summary
by MITRE • 04/18/2023
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Components Services). Supported versions that are affected are 8.0.32 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-2023-21962 represents a critical availability threat within Oracle MySQL Server versions 8.0.32 and earlier. This flaw resides within the Server: Components Services component of the MySQL database system, making it particularly concerning for organizations relying on MySQL for their data infrastructure. The vulnerability's classification as easily exploitable indicates that attackers with minimal technical expertise can leverage this weakness, though it requires high privileged access and network connectivity through multiple protocols. The attack vector specifically targets network-based exploitation, meaning that adversaries can potentially compromise MySQL servers from remote locations, making this threat particularly dangerous in environments where database servers are exposed to external networks. The CVSS 3.1 scoring system assigns this vulnerability a base score of 4.9, which falls into the medium severity category, but the availability impact rating of high (A:H) underscores the potential for significant operational disruption. The attack complexity is rated as low (AC:L), suggesting that the exploitation process does not require extensive technical knowledge or resources, while the privilege requirement is high (PR:H), indicating that attackers must already possess elevated access levels within the system.
The technical nature of this vulnerability manifests as a flaw in how MySQL Server handles certain component services, leading to potential denial of service conditions that can cause complete system crashes or frequent restarts. When successfully exploited, the vulnerability allows attackers to either hang the MySQL Server process or create conditions that result in repeated crashes, effectively rendering the database service unavailable to legitimate users and applications. This behavior directly impacts the availability aspect of the CIA triad, which is particularly severe in database environments where uptime and reliability are paramount for business operations. The vulnerability's impact is not limited to simple service disruption but can potentially cause complete system outages that may affect multiple applications and services dependent on the compromised MySQL instance. The fact that this vulnerability affects the core components services within MySQL means that the exploitation could potentially compromise fundamental system functions that maintain database integrity and access control mechanisms. This type of flaw aligns with CWE-119, which deals with memory safety issues, and may also relate to CWE-400, representing unspecified resource management vulnerabilities. The attack pattern suggests that the vulnerability could be exploited through protocol-level interactions that the MySQL server accepts, potentially through multiple network protocols that the server supports for database communication.
From an operational standpoint, the impact of CVE-2023-21962 extends beyond immediate service disruption to encompass broader business continuity concerns. Organizations using affected MySQL versions face the risk of extended downtime that can affect critical business processes, customer access to services, and overall system reliability. The high availability impact rating means that even a single successful exploitation attempt could cause significant operational damage, particularly in environments where database services are mission-critical. The vulnerability's potential to cause repeated crashes creates additional operational challenges as system administrators may face continuous disruption requiring frequent intervention and recovery efforts. The requirement for high privileged access, while limiting the attack surface, does not eliminate the threat since privileged accounts are often targeted in security breaches, and the low attack complexity makes exploitation more likely to succeed in real-world scenarios. Organizations with exposed MySQL servers may find themselves dealing with automated attacks that target this specific vulnerability, leading to potential cascading failures if database services are integral to larger application ecosystems. The vulnerability's presence in versions up to 8.0.32 indicates that a substantial portion of MySQL deployments could be affected, particularly in environments where regular patching cycles are not maintained or where legacy systems are still in operation.
The recommended mitigation strategies for CVE-2023-21962 primarily focus on immediate patching and system hardening measures. Organizations should prioritize upgrading to MySQL Server versions that contain the fix for this vulnerability, specifically versions beyond 8.0.32 where the vulnerability has been addressed. The patching process should be carefully planned to minimize operational disruption while ensuring that all affected systems receive the necessary updates. Network segmentation and access controls should be implemented to limit exposure of MySQL servers to untrusted networks, reducing the attack surface for this vulnerability. Regular monitoring of database server processes should be established to detect unusual behavior patterns that might indicate exploitation attempts. Additionally, implementing intrusion detection systems that can identify protocol-based attacks targeting MySQL services can provide early warning capabilities. The mitigation approach should also include regular security assessments of database environments to identify other potential vulnerabilities that could be exploited in conjunction with this flaw. Organizations should consider implementing database activity monitoring solutions that can detect abnormal access patterns or resource consumption that might indicate exploitation attempts. The vulnerability's classification as a denial of service threat means that traditional security measures like firewalls and IDS systems may not be sufficient, requiring more sophisticated monitoring and response capabilities. System administrators should also establish incident response procedures specifically addressing database service disruptions, ensuring that recovery processes can be executed quickly and effectively when exploitation occurs. The remediation process must account for potential compatibility issues that might arise from patching database systems, particularly in complex enterprise environments where multiple applications depend on specific MySQL configurations and features.