CVE-2011-2743 in Chyrp
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in Chyrp 2.1 and earlier allow remote attackers to inject arbitrary web script or HTML via the action parameter to (1) the default URI or (2) includes/javascript.php, or the (3) title or (4) body parameter to admin/help.php.
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Analysis
by VulDB Data Team • 12/07/2024
The CVE-2011-2743 vulnerability represents a critical cross-site scripting flaw affecting Chyrp version 2.1 and earlier systems. This vulnerability resides in the web application's input validation mechanisms, specifically within the administrative interfaces where user-supplied data is not properly sanitized before being rendered back to users. The flaw manifests when the application fails to adequately filter or escape user-controllable parameters, creating opportunities for malicious actors to inject arbitrary HTML or JavaScript code into web pages viewed by other users. The vulnerability impacts multiple endpoints including the default URI handling, javascript.php script, and the admin/help.php interface where title and body parameters are processed without sufficient security controls.
The technical exploitation of this vulnerability occurs through the manipulation of specific HTTP parameters that are directly processed by the Chyrp application's backend. Attackers can craft malicious requests targeting the action parameter in the default URI context or the includes/javascript.php endpoint, or alternatively target the title and body parameters within admin/help.php. These parameters are typically used for legitimate administrative functions such as content management or JavaScript inclusion, but the lack of proper input sanitization allows attackers to inject malicious scripts that execute in the context of other users' browsers. The vulnerability operates under CWE-79 which specifically addresses Cross-Site Scripting flaws in software applications, making it a well-documented and severe security weakness in web application development practices.
The operational impact of CVE-2011-2743 extends beyond simple data theft or defacement, as it enables attackers to establish persistent malicious presence within the application environment. Successful exploitation allows adversaries to execute arbitrary code in victims' browsers, potentially leading to session hijacking, credential theft, or redirection to malicious sites. The vulnerability's presence in administrative interfaces particularly amplifies its danger, as it could enable attackers to gain elevated privileges or compromise the entire content management system. According to ATT&CK framework categorization, this vulnerability maps to T1566.001 (Phishing via Social Engineering) and T1059.007 (Command and Scripting Interpreter: JavaScript) as attackers can leverage the XSS to deliver malicious payloads that exploit other attack vectors. The flaw essentially transforms the web application into a potential attack vector for broader compromise of the web environment.
Mitigation strategies for CVE-2011-2743 require immediate attention through multiple defensive layers. The primary solution involves implementing proper input validation and output encoding mechanisms across all user-controllable parameters, particularly those used in administrative functions. Organizations should apply the vendor's official patch or upgrade to Chyrp version 2.2 or later where the vulnerability has been addressed. Additionally, implementing Content Security Policy headers, input sanitization libraries, and regular security code reviews can prevent similar vulnerabilities from emerging in future development cycles. Network-based protections such as web application firewalls should also be configured to detect and block suspicious parameter patterns commonly associated with XSS attacks. The vulnerability serves as a critical reminder of the importance of secure coding practices, particularly in applications handling administrative functions, and demonstrates the necessity of regular vulnerability assessments to identify and remediate security weaknesses before they can be exploited in real-world scenarios.