CVE-2020-19626 in Craft
Summary
by MITRE
Cross Site Scripting (XSS) vulnerability in craftcms 3.1.31, allows remote attackers to inject arbitrary web script or HTML, via /admin/settings/sites/new.
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Analysis
by VulDB Data Team • 04/05/2021
The vulnerability identified as CVE-2020-19626 represents a critical cross site scripting flaw within Craft CMS version 3.1.31 that specifically affects the administrative settings section of the content management platform. This vulnerability exists in the endpoint /admin/settings/sites/new which is used to create new sites within the CMS configuration. The flaw enables remote attackers to inject malicious web scripts or HTML content into the application's administrative interface, potentially compromising the security of the entire content management system. The vulnerability stems from insufficient input validation and output sanitization mechanisms within the site creation form processing logic. Attackers can exploit this weakness by crafting malicious payloads that are then executed in the context of other users who access the affected administrative interface. This type of vulnerability falls under the CWE-79 category of Cross Site Scripting, which is classified as a critical security weakness in web applications. The ATT&CK framework categorizes this as a code injection technique that can lead to privilege escalation and persistent access to the compromised system. The vulnerability is particularly dangerous because it targets the administrative settings area where privileged users typically perform sensitive configuration tasks.
The technical exploitation of CVE-2020-19626 occurs when an attacker submits malicious input through the site creation form at the /admin/settings/sites/new endpoint. The application fails to properly sanitize user-supplied data before rendering it in the web page context, allowing attackers to inject JavaScript code or HTML tags that execute in the browser of authenticated users. This injection can occur in various fields of the site creation form including site names, URLs, or other configuration parameters that are rendered back to the user interface. The vulnerability persists because the CMS does not implement adequate content security policies or input validation measures that would prevent the execution of malicious code. When a privileged user accesses the administrative interface and views the affected site configuration, the injected scripts execute in their browser context, potentially leading to session hijacking, data exfiltration, or further compromise of the CMS environment. The impact extends beyond simple script execution as attackers can leverage this vulnerability to perform actions on behalf of legitimate users, potentially gaining unauthorized access to sensitive system configurations or content.
The operational impact of this vulnerability is severe and multifaceted across multiple security domains. Organizations using Craft CMS 3.1.31 are at risk of unauthorized access to their content management systems, potentially leading to complete compromise of their digital assets and user data. The vulnerability can enable attackers to establish persistent backdoors within the CMS environment, allowing them to maintain access over extended periods. Furthermore, the exploitation of this XSS vulnerability can facilitate more advanced attacks such as credential theft, session manipulation, and privilege escalation within the CMS framework. The attack surface is particularly concerning because the vulnerability affects the administrative interface where critical system configurations are managed, potentially allowing attackers to modify site settings, create new administrative accounts, or alter content. Security teams must consider the implications of this vulnerability in relation to their incident response procedures and may need to perform comprehensive security assessments of their CMS environments. The vulnerability also impacts the integrity of the content management system's data and can lead to reputational damage if attackers use the compromised system to deface websites or distribute malicious content to end users.
Mitigation strategies for CVE-2020-19626 require immediate action to address the underlying XSS vulnerability through proper input validation and output encoding mechanisms. Organizations should upgrade to Craft CMS version 3.1.32 or later, which contains the necessary patches to resolve this vulnerability. The upgrade process should include thorough testing to ensure compatibility with existing site configurations and content management workflows. Additionally, implementing proper content security policies can provide an additional layer of defense against similar vulnerabilities. Security teams should also consider deploying web application firewalls that can detect and block malicious payloads targeting XSS vulnerabilities in the administrative interface. Regular security audits and input validation testing of all CMS forms and administrative endpoints are essential to prevent similar vulnerabilities from emerging in the future. The implementation of proper output encoding mechanisms for all user-supplied data that is rendered in web pages will help prevent the execution of malicious scripts. Organizations should also establish monitoring procedures to detect potential exploitation attempts and maintain detailed logs of administrative activities for forensic analysis. The vulnerability serves as a reminder of the importance of maintaining current security patches and implementing comprehensive security controls across all application components, particularly those handling privileged administrative functions. Regular vulnerability assessments and security training for administrators can help reduce the risk of successful exploitation of such vulnerabilities.