CVE-2026-73477 in Quick Tabs Plugin
Summary
by MITRE • 09/02/2026
Incorrect Authorization vulnerability in Drupal Quick Tabs allows Forceful Browsing. This issue affects Quick Tabs versions: from 0.0.0 to 4.3.1.
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Analysis
by VulDB Data Team • 09/02/2026
The security flaw identified within the Drupal Quick Tabs module, specifically affecting versions ranging from 0.0.0 through 4.3.1, represents a critical failure in access control mechanisms that enables unauthorized users to perform forceful browsing against protected administrative or restricted content areas. This vulnerability stems directly from an incorrect authorization check implemented during the request handling process for specific endpoints managed by the module. In a properly secured web application, every action that modifies state or exposes sensitive data must be preceded by rigorous verification of the user's permissions relative to the requested resource. However, in this instance, the module fails to adequately validate whether the authenticated user possesses the necessary privileges before processing requests intended for administrative configuration or restricted tab management features. This oversight allows attackers who have valid but low-privilege accounts, such as basic subscribers or editors without administrator rights, to bypass expected restrictions and interact with functionality reserved exclusively for users with higher clearance levels.
From a technical perspective, this vulnerability is classified under CWE-269, which denotes Improper Privilege Management, specifically manifesting as an elevation of privilege through insufficient access control checks. The root cause lies in the module's reliance on Drupal’s core permission system without implementing additional contextual validation for its specific API endpoints or form submissions. When a user submits a request to modify tab configurations, view restricted content settings, or execute administrative actions via the Quick Tabs interface, the backend logic does not sufficiently verify that the requester holds the 'administer quick tabs' permission or equivalent high-level access rights required by Drupal’s core architecture for such operations. Consequently, an attacker can craft HTTP requests targeting these endpoints directly, effectively circumventing the user interface restrictions designed to prevent unauthorized interaction. This type of flaw is often exploited through manual scripting tools or automated vulnerability scanners that systematically probe for misconfigured authorization rules across various modules within a CMS environment.
The operational impact of this vulnerability extends beyond simple data exposure, as it fundamentally compromises the integrity and confidentiality of the Drupal site’s administrative functions. An attacker leveraging this forceful browsing capability can alter tab configurations, potentially injecting malicious content or disrupting the user experience by reordering or hiding critical navigation elements. More severely, depending on how other modules interact with Quick Tabs, an attacker might exploit chained vulnerabilities to achieve remote code execution if certain configuration changes trigger insecure callbacks or file operations. Even in isolation, the ability to manipulate administrative settings without proper authorization undermines trust in the platform’s security model and can lead to significant reputational damage for organizations relying on Drupal for their web presence. Furthermore, this flaw facilitates further reconnaissance activities by allowing attackers to map out internal structures and identify additional attack vectors that would otherwise remain hidden behind authentication walls.
To mitigate this risk, immediate action is required to update the Quick Tabs module to a version later than 4.3.1 where these authorization checks have been corrected. Site administrators should verify their current installation status through Drupal’s official reporting tools or by inspecting the installed modules list within the administrative dashboard. In environments where updating is not immediately feasible due to compatibility constraints with other contributed themes or modules, temporary mitigations include restricting access to the affected endpoints via web application firewall rules that block unauthorized POST requests to specific paths associated with Quick Tabs administration. Additionally, enforcing strict role-based access control policies and regularly auditing user permissions can help minimize the attack surface by ensuring that only trusted individuals have accounts capable of interacting with administrative interfaces. Regular security audits and penetration testing are recommended to identify similar authorization flaws in other modules before they can be exploited in production environments.