CVE-2020-14852 in MySQL Server
Summary
by MITRE • 10/21/2020
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Charsets). Supported versions that are affected are 8.0.21 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).
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 11/24/2020
The vulnerability identified as CVE-2020-14852 resides within the MySQL Server component responsible for character set handling, specifically affecting versions 8.0.21 and earlier. This weakness falls under the broader category of software flaws that can compromise system availability and stability. The vulnerability is classified as easily exploitable, indicating that attackers with relatively low technical barriers can leverage it effectively. The affected component operates within the server-side processing of character encoding, which is fundamental to database operations and data handling across various protocols.
The technical flaw manifests in the way MySQL Server processes certain character set operations, creating conditions where malicious input can trigger abnormal termination sequences. This particular vulnerability operates at a privilege level that requires high privileges for exploitation, suggesting that attackers must already possess elevated access rights within the network environment. The attack vector utilizes multiple network protocols, expanding the potential attack surface and making the vulnerability more accessible across different network configurations. The underlying mechanism appears to involve improper handling of character encoding sequences that can lead to memory corruption or resource exhaustion conditions.
The operational impact of this vulnerability is significant as it can result in complete denial of service conditions for the affected MySQL Server instances. Successful exploitation can cause the database server to hang indefinitely or experience frequently repeatable crashes, effectively rendering the database service unavailable to legitimate users and applications. This type of availability impact directly affects business continuity and can result in substantial operational disruptions, particularly in environments where database availability is critical for application functionality. The CVSS base score of 4.9 reflects the moderate to high severity of the availability impact, with the vector indicating network accessibility, low attack complexity, high privileges required, and no user interaction needed.
Organizations should prioritize patch management to address this vulnerability through the official Oracle MySQL security updates. The remediation process involves upgrading to MySQL Server versions that have been patched to resolve the character set handling issues. Network segmentation and access control measures can provide additional defense-in-depth layers, limiting the potential attack surface for privilege escalation scenarios. Monitoring systems should be configured to detect unusual patterns in database server behavior that might indicate exploitation attempts. The vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and may relate to ATT&CK techniques involving service stoppage and denial of service operations. Regular security assessments and vulnerability scanning should include verification of MySQL Server character set configurations to prevent exploitation.