CVE-2020-14620 in MySQL Server
Summary
by MITRE
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: DML). Supported versions that are affected are 8.0.20 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 • 11/02/2020
The vulnerability identified as CVE-2020-14620 represents a critical availability threat within Oracle MySQL Server versions 8.0.20 and earlier, specifically affecting the Server: DML component. This flaw manifests as a denial of service condition that can be exploited by attackers with high privileges and network access through multiple protocols. The vulnerability's classification as easily exploitable indicates that malicious actors can readily leverage this weakness without requiring specialized tools or extensive technical knowledge. The CVSS 3.1 scoring system assigns it a base score of 4.9, reflecting the significant availability impact that can result from successful exploitation, with the vector AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H indicating network accessibility with low attack complexity, high privilege requirements, and universal scope.
The technical nature of this vulnerability stems from improper handling of certain DML operations within the MySQL Server architecture, specifically within the server component responsible for data manipulation language processing. When exploited, the vulnerability allows an attacker to trigger conditions that cause the MySQL server process to hang or repeatedly crash, effectively rendering the database service unavailable to legitimate users. This type of vulnerability typically arises from inadequate input validation, memory management issues, or flawed state handling within the server's processing logic. The fact that this affects the DML component suggests the issue occurs during data modification operations such as INSERT, UPDATE, or DELETE commands, where malformed or specially crafted inputs can cause the server to enter an unstable state.
From an operational standpoint, this vulnerability presents a significant risk to database availability and business continuity, particularly in environments where MySQL serves as a critical backend service. The complete denial of service condition can result in extended downtime for applications dependent on the database, potentially causing cascading failures throughout the enterprise infrastructure. Organizations running affected MySQL versions face the immediate risk of service disruption, which could impact customer-facing applications, transaction processing, and data integrity operations. The high privilege requirement for exploitation means that attackers typically need to have legitimate access to the system or have already compromised a privileged account, making this vulnerability particularly dangerous in environments where privilege escalation attacks are possible.
Security professionals should prioritize patching affected MySQL Server installations to address this vulnerability, as Oracle has released patches to remediate the issue. The mitigation strategy should include comprehensive testing of patches in staging environments before deployment to production systems to ensure compatibility with existing applications and workflows. Organizations should also implement network segmentation and access controls to limit the attack surface, particularly for MySQL servers that are exposed to untrusted networks. Monitoring for unusual patterns of database connection failures or process restarts can help detect exploitation attempts. This vulnerability aligns with CWE-121, which covers stack-based buffer overflow conditions, and may relate to ATT&CK technique T1499.004 for network denial of service attacks, highlighting the importance of maintaining up-to-date security patches and implementing robust monitoring procedures to protect against such availability-focused threats.