CVE-2006-5664 in Informix Dynamic Server
Summary
by MITRE
The installation script in IBM Informix Dynamic Server 10.00, Informix Client Software Development Kit (CSDK) 2.90, and Informix I-Connect 2.90 allows local users to "compromise security" via a symlink attack on temporary files.
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Analysis
by VulDB Data Team • 04/26/2026
The vulnerability identified as CVE-2006-5664 represents a critical security flaw in IBM Informix Dynamic Server and related components that stems from improper handling of temporary files during installation processes. This issue affects versions 10.00 of Informix Dynamic Server, 2.90 of Informix Client Software Development Kit, and 2.90 of Informix I-Connect, creating a pathway for local attackers to escalate privileges and compromise system security through a well-known attack vector. The vulnerability specifically targets the installation scripts that fail to properly validate or secure temporary file operations, leaving the system exposed to symlink-based attacks that can be exploited by malicious users with local access.
The technical implementation of this vulnerability involves the installation scripts creating temporary files without adequate security measures to prevent symbolic link manipulation. When these scripts execute, they may create temporary files in predictable locations without proper file ownership or permission checks. An attacker with local access can establish symbolic links in the same directories where these temporary files are expected to be created, effectively redirecting the installation process to modify files that the attacker controls rather than the intended system files. This type of attack falls under the category of race condition vulnerabilities and improper file handling, which are commonly classified as CWE-377 and CWE-378 within the CWE database. The attack leverages the principle of least privilege violation by allowing local users to manipulate system installation processes and potentially gain elevated privileges.
The operational impact of CVE-2006-5664 extends beyond simple privilege escalation to encompass broader system compromise potential. When exploited successfully, this vulnerability can enable attackers to modify critical system files, install malicious software, or alter configuration settings that affect database operations and data integrity. The vulnerability affects the fundamental security posture of systems running affected IBM Informix products, particularly in environments where local user access is not strictly controlled. Organizations may experience unauthorized access to sensitive data, modification of database configurations, or potential denial of service conditions when the installation process is compromised. This vulnerability particularly impacts enterprise environments where database administrators may execute installation scripts with elevated privileges, creating a window of opportunity for attackers to exploit the insecure temporary file handling mechanisms.
Mitigation strategies for CVE-2006-5664 require immediate implementation of security hardening measures and proper system administration practices. Organizations should immediately apply available vendor patches and updates from IBM to address the vulnerable installation scripts and temporary file handling mechanisms. System administrators must ensure that installation processes run with minimal required privileges and that temporary file locations are properly secured with appropriate permissions and ownership settings. The implementation of proper file system permissions, including the use of secure temporary directories with restricted write access, can prevent symlink attacks from succeeding. Additionally, organizations should conduct thorough security assessments of their database environments to identify any other potential vulnerabilities in related software components and ensure proper access controls are maintained. This vulnerability aligns with several ATT&CK techniques including privilege escalation and defense evasion, making it a critical concern for organizations implementing comprehensive security monitoring and incident response procedures. The remediation process should include verification that the installation scripts no longer create insecure temporary files and that proper security controls are in place to prevent similar vulnerabilities from being introduced in future versions of the software.