CVE-2006-4226 in MySQL
Summary
by MITRE
MySQL before 4.1.21, 5.0 before 5.0.25, and 5.1 before 5.1.12, when run on case-sensitive filesystems, allows remote authenticated users to create or access a database when the database name differs only in case from a database for which they have permissions.
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Analysis
by VulDB Data Team • 06/24/2019
This vulnerability exists in multiple versions of the MySQL database management system and represents a significant authorization bypass flaw that exploits case sensitivity differences in filesystems. The vulnerability affects MySQL versions prior to 4.1.21, 5.0.25, and 5.1.12 when operating on filesystems that distinguish between uppercase and lowercase letters. The core issue arises from how MySQL handles database name comparisons in case-sensitive environments, creating a scenario where users can gain unauthorized access to databases through carefully crafted case variations. This weakness falls under the CWE-284 category of Improper Access Control, specifically involving insufficient authorization checks during database operations. The vulnerability is particularly dangerous because it allows authenticated users to escalate their privileges by leveraging the case-insensitive nature of database name handling in certain contexts while maintaining case-sensitive filesystem operations.
The technical flaw manifests when MySQL processes database creation or access requests on case-sensitive filesystems where a user has permissions for one database name but attempts to access or create a database with the same name in different case. For instance, if a user has permissions for a database named "MyDatabase", they could potentially create or access a database named "mydatabase" or "MYDATABASE" on a case-sensitive filesystem, effectively bypassing the intended access controls. This occurs because MySQL's internal database name resolution logic does not properly account for case differences when validating user permissions, creating a gap between the expected security boundaries and actual implementation. The vulnerability is classified as a privilege escalation issue that can lead to unauthorized data access, modification, or deletion within the targeted database systems. This flaw directly maps to ATT&CK technique T1078.004 for Valid Accounts and T1484.001 for Privilege Escalation through abuse of database permissions.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it can enable attackers to perform data manipulation, information disclosure, and potentially compromise the integrity of database operations. An authenticated attacker with minimal permissions could exploit this vulnerability to gain access to sensitive information stored in databases they should not be able to reach, effectively undermining the database security model. The risk is amplified in environments where multiple users have varying levels of database access, as the vulnerability could allow lower-privileged users to access databases containing confidential or critical information. This weakness can be particularly problematic in enterprise environments where database security is paramount and where compliance requirements mandate strict access controls. Organizations running affected MySQL versions on case-sensitive filesystems face significant security risks, as this vulnerability can be exploited without requiring additional attack vectors or elevated privileges. The vulnerability also impacts database audit and logging capabilities, as access patterns may appear legitimate while actually representing unauthorized access attempts. System administrators must consider this vulnerability when implementing security controls and access management policies, particularly in environments where database security is a primary concern. The affected versions represent a substantial portion of MySQL installations, making this vulnerability particularly widespread and impactful across various deployment scenarios.