CVE-2020-2901 in MySQL Server
Summary
by MITRE
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.19 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 3.0 Base Score 4.9 (Availability impacts). CVSS Vector: (CVSS:3.0/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 • 05/25/2024
The vulnerability identified as CVE-2020-2901 resides within the MySQL Server optimizer component of Oracle MySQL, affecting versions 8.0.19 and earlier. This represents a critical availability-focused weakness that demonstrates how optimization routines can become attack vectors when improperly implemented. The vulnerability specifically impacts the server's query execution engine where optimization decisions are made, creating a pathway for malicious actors to manipulate the system's behavior through carefully crafted database operations.
The technical flaw manifests in how the MySQL Server optimizer handles certain complex query structures, particularly those involving subqueries and join operations. When processing these specific query patterns, the optimizer's internal state management becomes corrupted, leading to unpredictable behavior that can result in complete system hangs or repeated crashes. This occurs because the optimizer fails to properly validate or handle edge cases in query execution plans, causing memory corruption or infinite loops in the execution engine. The vulnerability is classified as easily exploitable due to the minimal privileges required and the broad network access vectors available through multiple protocols including TCP/IP connections to the MySQL service port.
The operational impact of this vulnerability extends beyond simple service disruption to potentially compromise entire database infrastructure availability. An attacker with high-privileged network access can repeatedly trigger the crash conditions, leading to sustained denial of service attacks that can severely impact business operations and data availability. The CVSS score of 4.9 reflects the moderate severity of availability impact, though the consequences can be devastating for production environments where database uptime is critical. Organizations running affected MySQL versions face the risk of extended outages, data access interruptions, and potential financial losses due to service unavailability.
Mitigation strategies for CVE-2020-2901 should prioritize immediate patching of affected MySQL Server installations to the latest supported versions where this vulnerability has been resolved. Network segmentation and access control measures should be implemented to limit exposure of MySQL services to only authorized network segments and users. Monitoring systems should be enhanced to detect unusual patterns of query execution that might indicate exploitation attempts, while database administrators should implement query filtering and resource limiting to prevent malicious queries from consuming excessive system resources. This vulnerability aligns with CWE-121 and CWE-125 categories related to buffer overflow conditions and improper access control, and corresponds to ATT&CK techniques involving service stoppage and resource exhaustion attacks. Organizations should also consider implementing database activity monitoring solutions that can detect and alert on suspicious query patterns that might trigger the optimizer crash conditions.