CVE-2006-4256 in Application Framework
Summary
by MITRE
index.php in Horde Application Framework before 3.1.2 allows remote attackers to include web pages from other sites, which could be useful for phishing attacks, via a URL in the url parameter, aka "cross-site referencing." NOTE: some sources have referred to this issue as XSS, but it is different than classic XSS.
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Analysis
by VulDB Data Team • 06/24/2019
The vulnerability described in CVE-2006-4256 represents a significant security flaw in the Horde Application Framework version 3.1.1 and earlier, where the index.php script fails to properly validate user input parameters. This weakness enables remote attackers to manipulate the url parameter to include external web pages, creating a dangerous cross-site referencing condition that can be exploited for malicious purposes. The vulnerability specifically affects the framework's handling of URL parameters without adequate sanitization or validation mechanisms, allowing attackers to inject external resources into the application's response.
This security issue falls under the category of insecure direct object references and cross-site request forgery vulnerabilities, with the technical flaw residing in the application's failure to implement proper input validation and sanitization for the url parameter. The vulnerability operates by accepting user-supplied URLs without verifying their legitimacy or origin, which creates an opportunity for attackers to redirect users to malicious sites. The flaw is particularly concerning because it enables phishing attacks where victims might be tricked into believing they are visiting legitimate application pages while actually being directed to attacker-controlled domains. The vulnerability differs from classic cross-site scripting attacks because it involves the inclusion of external web pages rather than the execution of malicious scripts within the browser context.
The operational impact of this vulnerability extends beyond simple phishing attempts to encompass broader security risks including credential theft, data exfiltration, and potential compromise of user sessions. Attackers can leverage this flaw to create convincing fake login pages or malicious content that appears to originate from trusted sources within the Horde framework. The vulnerability is particularly dangerous in enterprise environments where users trust the application's interface and may not recognize the difference between legitimate and malicious content. Security professionals should note that this vulnerability can be exploited to undermine user trust and potentially gain unauthorized access to sensitive information, making it a critical concern for organizations relying on the affected framework versions.
Mitigation strategies for CVE-2006-4256 should focus on implementing strict input validation and parameter sanitization for all URL parameters within the Horde Application Framework. Organizations should immediately upgrade to version 3.1.2 or later where this vulnerability has been addressed through proper URL validation mechanisms. Security measures should include implementing a whitelist approach for allowed URLs, ensuring that only trusted domains can be referenced, and implementing proper content security policies to prevent unauthorized resource inclusion. The solution aligns with security best practices outlined in the OWASP Top Ten and follows the principle of least privilege by restricting external resource access. Additionally, organizations should conduct thorough security testing to identify similar vulnerabilities in other application components and implement comprehensive monitoring to detect potential exploitation attempts. The vulnerability demonstrates the importance of proper input validation as outlined in CWE-20 and aligns with ATT&CK techniques related to initial access through malicious web content and credential access through phishing attacks.