CVE-2026-96356 in Webform Plugin
Summary
by MITRE • 10/22/2026
Incorrect Authorization vulnerability in Drupal Webform allows Forceful Browsing. This issue affects Webform versions: from 0.0.0 to 6.2.12, from 6.3.0 to 6.3.1.
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Analysis
by VulDB Data Team • 10/22/2026
The identified security flaw within the Drupal Webform module represents a critical failure in access control mechanisms, specifically categorized as an improper authorization vulnerability that facilitates forceful browsing or insecure direct object references. This issue impacts legacy versions of the module ranging from version 0.0.0 up to 6.2.12 and from 6.3.0 through 6.3.1. In these affected iterations, the application fails to adequately verify whether the authenticated user possesses the necessary privileges to access specific form data or administrative functions associated with webforms. Consequently, an attacker who has valid credentials can manipulate URL parameters or request identifiers to bypass intended restrictions and view, modify, or delete forms that are not authorized for their role. This type of vulnerability aligns directly with CWE-284, which describes Improper Access Control, and is frequently exploited using techniques documented in the MITRE ATT&CK framework under T1078, Valid Accounts, where attackers leverage legitimate credentials to access resources they should not be able to reach.
From a technical perspective, the root cause lies in the module's handling of user permissions during request processing for webform submissions and configurations. The code likely relies on implicit trust or incomplete checks when determining if a specific action is permissible based on the current session context. Instead of enforcing strict role-based access control policies at every point where sensitive data is retrieved or modified, the application allows requests to proceed without validating that the requester has explicit permission for that particular form instance. This oversight enables horizontal privilege escalation, allowing users with lower privileges to interact with resources belonging to other users or administrative sections intended only for site administrators. The lack of robust server-side validation means that client-side restrictions are insufficient as a primary defense mechanism, leaving the system vulnerable to automated tools designed to iterate through potential object identifiers and discover accessible endpoints.
The operational impact of this vulnerability is significant, particularly in environments where Drupal Webform handles sensitive personal information or confidential business data. Successful exploitation allows unauthorized users to exfiltrate private submission data, which may include personally identifiable information such as names, contact details, or financial records depending on the form fields configured by the site owner. Furthermore, if write permissions are also bypassed due to similar authorization gaps, attackers could inject malicious content into forms or delete existing submissions, leading to integrity violations and potential denial of service conditions for legitimate users. For organizations relying on these modules for customer engagement or internal workflows, such a breach undermines trust and may result in non-compliance with data protection regulations like GDPR or HIPAA if protected health information is exposed through this vector.
Mitigation strategies must prioritize immediate remediation by upgrading the Drupal Webform module to a version that resolves these authorization checks, ensuring that all access control logic adheres to secure coding standards. Administrators should verify their current installation against the specified vulnerable ranges and apply patches provided by the maintainers as soon as possible. In cases where an upgrade is not immediately feasible due to compatibility constraints with other modules or custom code, temporary mitigations include implementing strict firewall rules that restrict access to webform endpoints based on IP addresses if applicable, although this is less effective against authenticated attacks. Additionally, enhancing logging and monitoring for unusual patterns in form submissions can help detect exploitation attempts early. It is also advisable to conduct a thorough review of other modules within the Drupal ecosystem to ensure no similar authorization flaws exist, as attackers often chain multiple vulnerabilities to achieve deeper system compromise. Regular security audits and penetration testing focused on access control mechanisms are essential to maintain the integrity of web applications built on this platform.