CVE-2014-8746 in Skeleton theme
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in the Skeleton theme 7.x-1.2 through 7.x-1.3 before 7.x-1.4, for Drupal allows remote authenticated users with the "administer themes" permission to inject arbitrary web script or HTML via vectors related to theme settings.
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Analysis
by VulDB Data Team • 03/25/2018
The CVE-2014-8746 vulnerability represents a critical cross-site scripting flaw within the Drupal content management system's Skeleton theme component. This vulnerability specifically affects versions 7.x-1.2 through 7.x-1.3, before the release of 7.x-1.4, creating a window of exposure for Drupal installations that utilized this particular theme. The flaw resides in how the theme handles user input within its settings configuration, making it particularly dangerous as it can be exploited by authenticated users who possess administrative privileges. The vulnerability operates through a classic XSS vector where malicious scripts can be injected into theme settings, which then get executed when other users view the affected pages. This creates a significant risk for organizations that rely on Drupal's theme customization features, as the attack surface expands beyond simple content management to include theme configuration interfaces.
The technical exploitation of this vulnerability requires an attacker to possess the specific "administer themes" permission, which grants them access to modify theme settings within the Drupal administrative interface. This permission level typically belongs to site administrators or users with elevated privileges, but the impact remains severe due to the nature of XSS attacks. When an attacker successfully injects malicious code through theme settings, the payload executes in the context of other users' browsers who visit pages using the compromised theme. The vulnerability stems from inadequate input sanitization and output escaping mechanisms within the theme configuration handling code, allowing malicious script tags to persist in the database and subsequently render in the user's browser without proper sanitization. This weakness directly aligns with CWE-79, which categorizes cross-site scripting vulnerabilities as a fundamental web application security flaw where untrusted data is improperly escaped before being rendered in web pages.
The operational impact of CVE-2014-8746 extends beyond simple data theft or defacement, as it can enable attackers to execute arbitrary commands within victim browsers and potentially escalate their privileges further. Attackers can craft malicious payloads that steal session cookies, redirect users to phishing sites, or even inject additional malicious code that could lead to complete system compromise. The vulnerability is particularly dangerous in multi-user environments where administrators might unknowingly save malicious code in theme settings, creating a persistent threat that affects all users who access the site. This type of vulnerability also aligns with ATT&CK technique T1059.001, which covers command and scripting interpreter usage, as the injected scripts can execute commands within the browser context. The attack chain typically begins with privilege escalation or credential compromise to obtain the "administer themes" permission, followed by the injection of malicious payloads into theme configuration fields.
Organizations affected by this vulnerability should implement immediate mitigations including prompt upgrading to Drupal 7.x-1.4 or later versions where the XSS vulnerability has been patched. Additionally, administrators should review and tighten access controls to ensure that only trusted personnel possess the "administer themes" permission, implementing the principle of least privilege. Input validation should be enhanced at multiple layers, including database storage and output rendering, to prevent malicious code from persisting in theme settings. Security monitoring should be implemented to detect unusual theme configuration changes, and regular security audits should verify that theme settings are not being used as attack vectors. The vulnerability demonstrates the importance of proper input sanitization and output escaping practices as outlined in OWASP Top 10 security guidelines, particularly addressing the need for comprehensive validation of all user-provided data before it is processed or stored. Organizations should also consider implementing Content Security Policy headers to add an additional layer of protection against XSS attacks, though this should not replace proper input validation. Regular patch management procedures should be enforced to ensure timely application of security updates and prevent similar vulnerabilities from being exploited in the future.