CVE-2020-14799 in MySQL Server
Summary
by MITRE • 10/21/2020
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Security: Encryption). 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 • 11/24/2020
The vulnerability identified as CVE-2020-14799 represents a significant availability risk within Oracle MySQL Server versions 8.0.20 and earlier. This weakness resides in the Server: Security: Encryption component, specifically affecting the encryption mechanisms that protect data integrity and confidentiality. The vulnerability's classification as easily exploitable indicates that attackers with minimal technical sophistication can leverage this flaw, particularly when they possess high-privileged network access through multiple protocols. The attack vector requires network connectivity and elevated privileges, suggesting that internal threat actors or those who have already compromised administrative access pose the primary risk. The CVSS 3.1 scoring system rates this vulnerability at 4.9 out of 10, with the availability impact category receiving the highest weight, reflecting the potential for complete denial of service conditions that can render database services completely inaccessible.
The technical nature of this vulnerability stems from weaknesses in how MySQL Server handles encryption operations, particularly when processing specific encryption-related requests. Attackers can exploit this flaw by crafting malicious network requests that trigger improper handling of encryption contexts within the server process. The resulting behavior manifests as either system hangs or repeated crashes that can be triggered repeatedly, leading to sustained disruption of database services. This type of vulnerability typically involves improper input validation or resource management issues within the encryption subsystem, where insufficient error handling causes the server to enter unstable states when encountering malformed or specially crafted encryption parameters. The impact extends beyond simple service interruption, as the repeated nature of the crashes can prevent administrators from restoring service quickly, potentially leading to extended downtime and data accessibility issues for legitimate users.
The operational impact of CVE-2020-14799 extends beyond immediate service disruption to potentially compromise the overall reliability and availability of database infrastructure. Organizations relying on MySQL Server for critical business operations face significant risk of operational disruption, particularly in environments where database availability is paramount for business continuity. The vulnerability's ability to cause complete denial of service means that database applications may become completely inaccessible, affecting all dependent systems and potentially cascading into broader business impacts. The high privilege requirement for exploitation suggests that this vulnerability is more likely to be targeted by insider threats or attackers who have already gained administrative access to network resources, making it particularly dangerous in environments where privileged accounts are compromised. This scenario aligns with ATT&CK technique T1078 which covers valid accounts usage, where attackers leverage legitimate administrative credentials to perform malicious activities.
Security practitioners should prioritize patch management and immediate remediation of affected MySQL Server installations, particularly focusing on upgrading to versions beyond 8.0.20 where this vulnerability has been addressed. Network segmentation and access controls should be reinforced to limit the attack surface and reduce the likelihood of unauthorized access to privileged network resources. Monitoring systems should be enhanced to detect unusual patterns in database connection behavior or encryption-related error messages that might indicate exploitation attempts. The vulnerability's classification under CWE-20, which covers "Improper Input Validation," suggests that proper sanitization of encryption parameters and robust error handling mechanisms should be implemented as part of defensive measures. Organizations should also implement comprehensive incident response procedures that account for potential denial of service scenarios, ensuring that backup systems and failover mechanisms are available to maintain business continuity during exploitation attempts. Regular vulnerability assessments and penetration testing should include evaluation of encryption mechanisms to identify similar weaknesses that could be exploited for availability impact purposes.