CVE-2018-3062 in MySQL Server
Summary
by MITRE
Vulnerability in the MySQL Server component of Oracle MySQL (subcomponent: Server: Memcached). Supported versions that are affected are 5.6.40 and prior, 5.7.22 and prior and 8.0.11 and prior. Difficult to exploit vulnerability allows low privileged attacker with network access via memcached 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 3.0 Base Score 5.3 (Availability impacts). CVSS Vector: (CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H).
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Analysis
by VulDB Data Team • 04/17/2023
The vulnerability identified as CVE-2018-3062 affects the MySQL Server component with specific exposure in the Server: Memcached subcomponent. This issue impacts multiple version ranges including 5.6.40 and earlier, 5.7.22 and earlier, and 8.0.11 and earlier versions of the MySQL database system. The vulnerability resides within the memcached interface that MySQL utilizes for caching operations, creating a potential attack surface that could be exploited by malicious actors. The affected configuration specifically involves the integration between MySQL's native memcached protocol implementation and the underlying database server infrastructure, where the memcached plugin operates as an extension to the core MySQL service.
The technical flaw manifests as a memory corruption vulnerability within the memcached protocol handling code that processes incoming network requests. When a malicious actor sends specially crafted packets to the memcached interface, the system fails to properly validate input parameters, leading to buffer overflows or other memory management errors. This flaw is classified as difficult to exploit due to the requirement for network access and the need for an attacker to possess low privilege credentials to initiate the attack vector. The vulnerability operates through the memcached protocol port typically used for caching operations, where legitimate database clients and applications connect to the service for performance optimization purposes.
The operational impact of this vulnerability extends beyond simple service disruption to potentially cause complete denial of service conditions within the MySQL server environment. Successful exploitation can result in the MySQL server entering a state where it hangs or crashes repeatedly, effectively rendering the database service unavailable to legitimate users and applications. This availability impact represents a significant concern for production environments where database uptime is critical for business operations. The vulnerability's CVSS 3.0 score of 5.3 indicates a medium severity impact with the primary concern being the availability of services rather than confidentiality or integrity breaches, though the complete system downtime can indirectly affect overall security posture.
The attack scenario requires an attacker to have network connectivity to the memcached interface and possess minimal privileges to establish a connection. This attack vector aligns with the ATT&CK technique T1190 - Exploit Public-Facing Application, as it involves targeting exposed network services through protocol-based vulnerabilities. The vulnerability's classification under CWE-121 - Stack-based Buffer Overflow and CWE-125 - Out-of-bounds Read indicates that the memory management issues stem from improper bounds checking in the code handling memcached protocol requests. Organizations should implement network segmentation to limit access to memcached ports, disable unnecessary memcached functionality, and apply the appropriate security patches provided by Oracle. The CVSS vector (AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H) emphasizes that network-based attacks require high complexity but can be executed with low privilege levels, making this vulnerability particularly concerning for environments where network exposure cannot be completely eliminated.
Mitigation strategies should focus on immediate patch application for all affected MySQL versions, network access controls to restrict memcached interface exposure, and monitoring for anomalous connection patterns or service disruptions. The vulnerability demonstrates the importance of securing database interface components and highlights the need for comprehensive security assessments of all database server extensions and plugins. Organizations should also consider implementing intrusion detection systems to monitor for potential exploitation attempts targeting memcached protocol implementations. The vulnerability serves as a reminder of the critical importance of maintaining up-to-date database software and implementing defense-in-depth strategies that protect against various attack vectors targeting database infrastructure components.