CVE-2017-3636 in MySQL Server
Summary
by MITRE
Vulnerability in the MySQL Server component of Oracle MySQL (subcomponent: Client programs). Supported versions that are affected are 5.5.56 and earlier and 5.6.36 and earlier. Easily exploitable vulnerability allows low privileged attacker with logon to the infrastructure where MySQL Server executes to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized update, insert or delete access to some of MySQL Server accessible data as well as unauthorized read access to a subset of MySQL Server accessible data and unauthorized ability to cause a partial denial of service (partial DOS) of MySQL Server. CVSS 3.0 Base Score 5.3 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L).
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Analysis
by VulDB Data Team • 01/04/2021
The vulnerability identified as CVE-2017-3636 resides within the MySQL Server component of Oracle MySQL, specifically affecting client programs that interface with the database system. This flaw manifests in versions 5.5.56 and earlier, as well as 5.6.36 and earlier, representing a significant security weakness that impacts a substantial portion of MySQL deployments. The vulnerability operates at a fundamental level within the database communication protocols, creating an exploitable condition that can be leveraged by adversaries with minimal privileges.
The technical nature of this vulnerability stems from insufficient input validation within the client program interfaces of MySQL Server, allowing attackers to manipulate database communication streams. The flaw enables an attacker with valid login credentials to the MySQL server infrastructure to execute unauthorized operations against the database system. This includes the ability to modify data through unauthorized update, insert, or delete operations, while simultaneously gaining read access to sensitive database content. The vulnerability's classification as easily exploitable indicates that the attack vector requires minimal technical expertise and can be executed with standard login credentials.
From an operational perspective, the impact of this vulnerability extends beyond simple data compromise to include service disruption capabilities. Attackers can cause partial denial of service conditions that affect database availability, potentially disrupting business operations that depend on MySQL services. The CVSS 3.0 score of 5.3 reflects the balanced nature of the threat, with medium severity across confidentiality, integrity, and availability impacts. The attack vector assessment (AV:L) indicates local access requirements, while the low access complexity (AC:L) suggests that exploitation does not require specialized tools or extensive knowledge. The low privilege requirement (PR:L) means that even users with basic database access can leverage this vulnerability effectively.
The security implications of CVE-2017-3636 align with CWE-20, which describes improper input validation issues that allow attackers to manipulate system behavior through malformed inputs. This vulnerability demonstrates how client-side components can serve as attack vectors that extend beyond simple user interface concerns into core system integrity threats. Organizations implementing MySQL services face significant risk when operating vulnerable versions, as the attack surface expands to include not just database administrators but any user with legitimate access to the database infrastructure.
Mitigation strategies should focus on immediate version upgrades to patched MySQL releases that address the input validation deficiencies. System administrators must implement comprehensive patch management procedures to ensure all MySQL installations receive timely updates. Network segmentation and access control measures can provide additional defense-in-depth layers, limiting the potential impact of successful exploitation attempts. Regular security assessments of database environments should include checks for vulnerable MySQL versions, while monitoring systems should be configured to detect unusual database access patterns that might indicate exploitation attempts. The vulnerability also underscores the importance of principle of least privilege implementations, where database users are granted only necessary permissions to reduce the potential damage from compromised accounts. Organizations should consider implementing database activity monitoring solutions that can detect unauthorized data modification attempts and provide alerts for potential exploitation of this class of vulnerability.