CVE-2018-2771 in MySQL Server
Summary
by MITRE
Vulnerability in the MySQL Server component of Oracle MySQL (subcomponent: Server: Locking). Supported versions that are affected are 5.5.59 and prior, 5.6.39 and prior and 5.7.21 and prior. Difficult to exploit 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 3.0 Base Score 4.4 (Availability impacts). CVSS Vector: (CVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H).
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Analysis
by VulDB Data Team • 03/02/2023
The vulnerability identified as CVE-2018-2771 resides within the MySQL Server component, specifically within the Server: Locking subcomponent of Oracle MySQL database systems. This flaw affects multiple version lines including 5.5.59 and earlier, 5.6.39 and earlier, and 5.7.21 and earlier releases, representing a significant portion of the MySQL ecosystem that was operational during the affected time period. The vulnerability classification as difficult to exploit indicates that while the attack vector is not trivial, it does require specific conditions and privileged access to succeed. The CVSS 3.0 score of 4.4 reflects a moderate severity level with availability impacts, specifically targeting the ability to cause complete denial of service through hangs or repeated crashes of the MySQL server instance.
The technical nature of this vulnerability involves a flaw in the locking mechanism implementation within MySQL server operations. When exploited, this weakness allows an attacker with high privileges and network access through multiple protocols to trigger a condition that results in the MySQL server becoming unresponsive or crashing repeatedly. The locking subsystem is critical to database operations as it manages concurrent access to data resources, and any flaw in this mechanism can lead to cascading failures in database availability. The vulnerability's impact manifests as a complete denial of service condition where legitimate database operations cannot proceed due to the server being in a hung state or experiencing frequent crashes that prevent normal operation.
From an operational perspective, the implications of this vulnerability extend beyond simple service disruption to potentially affect business continuity and data availability for organizations relying on MySQL databases. The requirement for high privileged access means that the vulnerability is typically exploitable by internal attackers or those who have already compromised other system components, making it particularly concerning for environments where privilege escalation is possible. The fact that this vulnerability can be triggered through multiple protocols indicates that attackers have various potential attack vectors, including TCP/IP connections, Unix domain sockets, or other network interfaces that MySQL supports. Organizations using affected MySQL versions face the risk of sustained service interruptions that could impact applications dependent on database availability.
The attack surface for this vulnerability aligns with several ATT&CK framework techniques including privilege escalation and denial of service operations, while the underlying flaw corresponds to CWE-121, which addresses stack-based buffer overflow conditions. Organizations should prioritize applying patches and updates to MySQL server installations to address this vulnerability, particularly focusing on upgrading to versions that contain the fix for the locking mechanism implementation. Additionally, implementing network segmentation and access controls can help limit the potential impact of exploitation by reducing the attack surface available to potential adversaries. The vulnerability demonstrates the importance of maintaining up-to-date database software and implementing proper access controls to protect against privilege-based attacks that can lead to complete service disruption.