CVE-2002-0555 in Informix Web Datablade
Summary
by MITRE
IBM Informix Web DataBlade 4.12 unescapes user input even if an application has escaped it, which could allow remote attackers to execute SQL code in a web form even when the developer has attempted to escape it.
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Analysis
by VulDB Data Team • 06/21/2024
The vulnerability identified as CVE-2002-0555 represents a critical SQL injection flaw within IBM Informix Web DataBlade 4.12, specifically targeting the handling of user input in web applications. This issue stems from the software's improper processing of escaped input data, creating a scenario where even when developers implement proper input sanitization measures, the underlying system can still interpret and execute malicious SQL commands. The vulnerability occurs at the data processing layer where the Web DataBlade component fails to maintain the integrity of escaped input, effectively neutralizing the security controls that developers have implemented to protect against SQL injection attacks.
The technical flaw manifests when user input passes through the Web DataBlade processing pipeline where it undergoes a second unescaping operation regardless of whether the input has already been properly escaped by the application layer. This behavior creates a fundamental security gap where malicious payloads that were designed to be harmless due to escaping can be reactivated during the processing phase, allowing attackers to inject arbitrary SQL commands directly into web forms. The vulnerability is particularly concerning because it operates at a level below the application logic, making it difficult for developers to detect and address through conventional code review processes.
From an operational perspective, this vulnerability enables remote attackers to exploit web applications built on IBM Informix Web DataBlade 4.12 without requiring any special privileges or authentication. Attackers can craft malicious input that appears to be properly escaped but is subsequently reinterpreted by the Web DataBlade component, potentially leading to unauthorized data access, data modification, or complete system compromise. The impact extends beyond simple data theft as attackers could leverage this vulnerability to escalate privileges, execute arbitrary code, or perform denial of service attacks against the affected systems. This vulnerability directly maps to CWE-89, which represents SQL injection flaws, and aligns with ATT&CK technique T1190 for exploitation of remote services through SQL injection.
The security implications of this vulnerability are severe as it undermines the fundamental security controls that developers implement to protect against SQL injection attacks. Organizations using IBM Informix Web DataBlade 4.12 are particularly at risk since the vulnerability exists in the processing layer rather than the application code itself, meaning that even well-written applications can be compromised. Mitigation strategies should focus on immediate patching of the Web DataBlade component to address the improper input handling behavior, while also implementing additional defensive measures such as web application firewalls, input validation at multiple layers, and regular security assessments. Organizations should also consider implementing database activity monitoring and access controls to limit the potential damage from successful exploitation attempts. The vulnerability highlights the importance of understanding the complete data flow in web applications and the need for comprehensive security testing that examines not just application code but also the underlying platform components that process user input.