CVE-2013-0741 in Imagen
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in imagegen.ashx in Percipient Studios ImageGen before 2.9.0 for Umbraco CMS allows remote attackers to inject arbitrary web script or HTML via the font parameter.
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Analysis
by VulDB Data Team • 03/02/2019
The CVE-2013-0741 vulnerability represents a critical cross-site scripting flaw in the Percipient Studios ImageGen component for Umbraco CMS, specifically affecting versions prior to 2.9.0. This vulnerability resides in the imagegen.ashx handler which processes image generation requests and fails to properly sanitize user input passed through the font parameter. The flaw creates a significant security risk by allowing remote attackers to inject malicious web scripts or HTML content directly into the application's response, potentially compromising user sessions and data integrity.
The technical implementation of this vulnerability stems from insufficient input validation and output encoding within the ImageGen component's font parameter handling mechanism. When users provide font names or parameters through the web interface, the application fails to adequately sanitize these inputs before incorporating them into dynamically generated content. This lack of proper sanitization creates an XSS vector where attackers can embed malicious JavaScript code or HTML tags that execute in the context of other users' browsers. The vulnerability specifically targets the font parameter, which is commonly used in image generation processes where font selection might be passed through to underlying rendering components.
The operational impact of this vulnerability extends beyond simple script injection, creating potential for more severe consequences within the Umbraco CMS environment. Attackers could leverage this flaw to steal session cookies, perform unauthorized actions on behalf of users, redirect victims to malicious sites, or even execute persistent XSS attacks that could compromise the entire CMS infrastructure. The vulnerability affects all users interacting with the ImageGen functionality, making it particularly dangerous in multi-user environments where administrators might be tricked into executing malicious code through crafted font parameters. This risk is exacerbated by the fact that the vulnerability exists in the core image generation component, which is frequently used for creating dynamic content within CMS applications.
Mitigation strategies for CVE-2013-0741 should prioritize immediate version upgrades to Percipient Studios ImageGen 2.9.0 or later, which contains the necessary input sanitization patches. Organizations should implement comprehensive input validation at multiple layers, including application-level sanitization of font parameters and output encoding of all dynamic content. The implementation of Content Security Policy headers can provide additional protection against XSS exploitation by restricting script execution and limiting the attack surface. Security teams should also conduct thorough vulnerability assessments of all third-party components within the Umbraco CMS environment and establish monitoring protocols to detect potential exploitation attempts. This vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws, and represents a typical example of how insecure input handling can lead to persistent security vulnerabilities in web applications.
The attack vector for this vulnerability typically involves crafting malicious font parameter values that contain embedded JavaScript or HTML content, which are then processed by the vulnerable ImageGen component. Attackers may leverage this flaw through various means including phishing campaigns, compromised user accounts, or direct exploitation of vulnerable web applications. The vulnerability demonstrates the importance of proper input validation and output encoding practices, aligning with ATT&CK technique T1059.007 for command and scripting interpreter execution. Organizations should also consider implementing web application firewalls and regular security scanning to detect and prevent exploitation attempts targeting this specific vulnerability.