CVE-2018-3155 in MySQL Server
Summary
by MITRE
Vulnerability in the MySQL Server component of Oracle MySQL (subcomponent: Server: Parser). Supported versions that are affected are 5.7.23 and prior and 8.0.12 and prior. Easily exploitable vulnerability allows low privileged attacker with network access via multiple protocols to compromise MySQL Server. While the vulnerability is in MySQL Server, attacks may significantly impact additional products. 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 7.7 (Availability impacts). CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H).
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Analysis
by VulDB Data Team • 05/26/2023
The vulnerability identified as CVE-2018-3155 resides within the MySQL Server component, specifically within the Server: Parser subcomponent of Oracle MySQL software. This flaw affects multiple versions including all 5.7.x releases up to 5.7.23 and 8.0.x versions up to 8.0.12, representing a significant attack surface across widely deployed database systems. The vulnerability's classification as easily exploitable indicates that attackers with minimal privileges and network access can leverage this weakness, making it particularly dangerous in production environments where database servers are often accessible over networks.
The technical nature of this vulnerability stems from improper handling within the SQL parser, which processes incoming database queries and commands. When maliciously crafted SQL statements are processed through this parser, the flaw can trigger memory corruption or execution flow disruption that leads to system instability. The vulnerability's impact extends beyond simple data compromise as it specifically enables a complete denial of service condition where the MySQL Server becomes unresponsive or crashes repeatedly. This behavior aligns with CWE-121, which describes heap-based buffer overflow conditions that can lead to arbitrary code execution or system crashes, and is particularly concerning given the availability impact score of 7.7 in the CVSS 3.0 framework.
The operational impact of CVE-2018-3155 represents a critical threat to database availability and business continuity. An attacker with low privileges and network access can cause repeated crashes or hangs that effectively disable database services, leading to significant downtime for applications dependent on MySQL. This vulnerability's potential to affect additional products demonstrates how database server weaknesses can cascade through entire application stacks, as many applications rely on consistent database availability for their operations. The CVSS vector analysis reveals the attack surface characteristics with network access (AV:N) requiring low privileges (PR:L) and no user interaction (UI:N), while the scope being changed (S:C) indicates the impact can extend beyond the immediate target to other connected systems.
Mitigation strategies for this vulnerability should prioritize immediate patching of affected MySQL versions, with administrators upgrading to versions 5.7.24 or later and 8.0.13 or later where the parser flaw has been addressed. Network segmentation and access controls should be implemented to limit exposure, particularly restricting network access to database servers to only authorized hosts and users. Monitoring solutions should be deployed to detect unusual patterns of database server crashes or restarts that might indicate exploitation attempts. Additionally, implementing database firewalls or query filtering mechanisms can help prevent malicious SQL statements from reaching the vulnerable parser component, aligning with defensive techniques outlined in the MITRE ATT&CK framework for database attacks. Organizations should also conduct comprehensive vulnerability assessments to identify any other systems that might be impacted by similar parser-related vulnerabilities in their database infrastructure.