CVE-2026-118567 in Bulk Update User Roles Plugin
Summary
by MITRE • 10/30/2026
Incorrect Authorization vulnerability in Drupal Bulk Update User Roles allows Forceful Browsing. This issue affects Bulk Update User Roles versions: from 0.0.0 to 1.0.5.
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Analysis
by VulDB Data Team • 10/30/2026
The identified security flaw resides within the Drupal module known as Bulk Update User Roles, specifically impacting version ranges from 0.0.0 through 1.0.5. This vulnerability is classified under CWE-284, which denotes Improper Access Control, and manifests primarily as a form of Forceful Browsing or Insecure Direct Object Reference where the application fails to adequately verify whether an authenticated user possesses the necessary privileges to perform specific administrative actions on behalf of other users. The core technical deficiency lies in the module's handling of role assignment operations for multiple user accounts simultaneously. When an administrator initiates a bulk update operation, the backend logic processes requests to modify roles associated with various user IDs without sufficiently validating that the initiating session has explicit authorization to alter the profile data of every target account listed in the request payload. This oversight allows an attacker who possesses valid credentials with lower-level administrative permissions or even certain standard authenticated privileges to manipulate the access control lists of other users, potentially escalating their own rights or granting elevated roles such as administrator to unauthorized accounts by exploiting the lack of granular permission checks during the batch processing phase.
From a technical perspective, this vulnerability exploits the trust placed in client-side inputs and server-side session validation mechanisms that do not enforce strict object-level authorization controls. The module likely relies on broad role-based access control rules rather than checking individual user ownership or specific capability grants for each entity being modified. Consequently, an attacker can craft HTTP requests containing arbitrary user identifiers to assign high-privilege roles like Administrator to themselves or other compromised accounts. This bypasses the intended security boundary because the system accepts the request based on general administrative status without verifying if that status extends to modifying every individual record in the batch. The absence of these checks creates a significant gap in the application's defense-in-depth strategy, allowing for privilege escalation through indirect object references where the user ID parameter is manipulated or accepted without secondary authorization verification against the current session's permissions matrix.
The operational impact of this vulnerability is severe, as it directly compromises the integrity and confidentiality of the Drupal site's access control infrastructure. Successful exploitation enables an attacker to escalate privileges from a low-privileged account to full administrative control over the web application. This level of access grants the ability to execute arbitrary code, modify website content, steal sensitive user data including passwords and personal information, install malicious modules or themes, and potentially pivot into other systems within the network if further vulnerabilities exist in connected services. The impact extends beyond immediate system compromise as it undermines trust in the administrative interface, allowing for persistent backdoors that are difficult to detect without thorough auditing of role assignments and login logs. Furthermore, because bulk operations often affect multiple users simultaneously, an attacker could potentially grant elevated roles to a large number of accounts if they can identify valid user IDs, leading to widespread compromise of the platform's security posture.
To mitigate this vulnerability, immediate action is required by upgrading the Bulk Update User Roles module to version 1.0.6 or later, where these authorization checks have been corrected to ensure that users can only modify roles for accounts they are explicitly permitted to manage. In environments where updating is not immediately feasible, administrators should implement compensating controls such as restricting access to bulk update features via web application firewalls by monitoring and blocking suspicious patterns of user ID manipulation in POST requests. Additionally, enforcing strict role-based permissions within Drupal core settings can limit the exposure by ensuring that only users with specific high-level privileges like Access administration pages or Administer users have the ability to perform bulk operations. Regular auditing of user roles and active sessions is also recommended to detect any unauthorized changes resulting from potential exploitation attempts before they lead to full system compromise.