CVE-2020-14550 in MySQL Client
Summary
by MITRE
Vulnerability in the MySQL Client product of Oracle MySQL (component: C API). Supported versions that are affected are 5.6.48 and prior, 5.7.30 and prior and 8.0.20 and prior. Difficult to exploit vulnerability allows low privileged attacker with network access via multiple protocols to compromise MySQL Client. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Client. CVSS 3.1 Base Score 5.3 (Availability impacts). CVSS Vector: (CVSS:3.1/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 • 11/02/2020
The vulnerability identified as CVE-2020-14550 resides within the MySQL Client component, specifically within the C Application Programming Interface that governs client-server communications. This flaw affects multiple version streams of Oracle MySQL including the 5.6, 5.7, and 8.0 branches, with all versions prior to the specified patches being susceptible to exploitation. The vulnerability operates at the client-side interface level where the C API handles network protocols and client connections, making it a critical point of failure in database communication stacks. The affected versions represent a substantial portion of MySQL deployments across various enterprise environments where client applications interact with database servers through standard network protocols.
The technical nature of this vulnerability manifests as a flaw in the client-side processing that can be triggered through network-based attacks. Attackers with low privileges and network access can exploit this weakness to cause the MySQL Client application to enter a state of permanent hang or to repeatedly crash, effectively rendering the client functionality unusable. The vulnerability's classification as difficult to exploit indicates that while it requires some level of network access and specific conditions to trigger, it does not require elevated privileges beyond basic network connectivity. The C API implementation contains a processing error that does not properly handle certain input sequences or connection states, leading to memory management issues or state corruption that results in system instability. This type of flaw typically involves improper handling of buffer operations, connection state transitions, or protocol parsing that can be manipulated through crafted network requests.
The operational impact of CVE-2020-14550 extends beyond simple service disruption to potentially compromise entire database access workflows. When exploited successfully, the vulnerability can cause complete denial of service conditions where database clients become unresponsive and require manual intervention to restore functionality. This disruption affects not only individual user sessions but can cascade through applications that depend on MySQL client connectivity, potentially causing widespread service outages. The availability impact score of 5.3 indicates that while the vulnerability may not directly compromise data integrity or confidentiality, it creates significant operational challenges that can be exploited to disrupt business operations. Organizations relying on MySQL client applications for critical business processes face potential downtime and productivity losses when this vulnerability is exploited. The vulnerability's network accessibility means that it can be targeted from external networks without requiring physical access to the database infrastructure, making it particularly dangerous in cloud and distributed environments.
Mitigation strategies for this vulnerability should prioritize immediate patching of affected MySQL client installations across all supported versions. Organizations should implement network segmentation and access controls to limit exposure to potential attackers, particularly by restricting unnecessary network access to MySQL client interfaces. The implementation of intrusion detection systems can help identify suspicious network patterns that may indicate exploitation attempts. Security monitoring should focus on client-side connection behaviors and unusual crash patterns that could indicate exploitation. Additionally, organizations should consider implementing application-level firewalls or proxy solutions to filter and validate network traffic before it reaches the MySQL client components. The vulnerability aligns with CWE-121, which describes buffer overflow conditions, and maps to ATT&CK technique T1499.1 for network denial of service attacks. Regular security assessments and vulnerability scanning should include verification of MySQL client versions and patch status to ensure comprehensive protection against this and similar vulnerabilities.