CVE-2026-107262 in Advanced Filesystem
Summary
by MITRE • 10/30/2026
Cross-Site Request Forgery (CSRF) vulnerability in Drupal Advanced Filesystem allows Cross Site Request Forgery. This issue affects Advanced Filesystem versions: from 0.0.0 to 1.0.28.
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Analysis
by VulDB Data Team • 10/30/2026
The identified security flaw represents a classic Cross-Site Request Forgery vulnerability within the Drupal Advanced Filesystem module, specifically impacting version ranges from initial release up through version 1.0.28. This type of attack exploits the trust that a web application has in the user's browser to execute unintended commands on behalf of an authenticated user without their knowledge or consent. In this specific context, the vulnerability arises because the affected module fails to implement adequate anti-CSRF protections for state-changing operations related to file system management. When a user is logged into the Drupal administration interface and subsequently visits a malicious website crafted by an attacker, that site can automatically submit HTTP requests to the vulnerable Drupal instance using the victim's active session cookies. Because these requests appear legitimate to the server due to the presence of valid authentication tokens or session identifiers stored in the browser, they are processed as if they originated from the authenticated administrator rather than a malicious third party.
From a technical perspective, the root cause lies in the absence of synchronized CSRF tokens within forms and AJAX endpoints managed by the Advanced Filesystem module during this version range. Standard web application security practices dictate that any action which modifies server state must require a unique, unpredictable token tied to the user's session. Without such validation mechanisms, an attacker can construct HTML pages containing hidden form submissions or JavaScript-driven XMLHttpRequests that target internal Drupal API endpoints responsible for file uploads, deletions, or configuration changes. The browser automatically includes cookies associated with the Drupal domain in these requests, bypassing same-origin policy restrictions which are designed to prevent cross-site scripting but do not inherently protect against CSRF when session identifiers are used as primary authentication credentials. This allows an attacker to manipulate the state of the application by tricking the victim into performing actions such as uploading malicious files, deleting critical data, or altering system configurations that could compromise the integrity and availability of the web platform.
The operational impact of this vulnerability is significant for organizations relying on Drupal for content management and file storage services. An attacker with sufficient privileges to exploit CSRF can potentially upload executable scripts disguised as legitimate documents, leading to remote code execution if subsequent steps are taken to trigger those files. Alternatively, an attacker could delete essential configuration files or user-uploaded assets, resulting in a denial of service condition that disrupts business operations and data accessibility. Furthermore, the ability to modify file permissions or alter system settings through CSRF can lead to privilege escalation scenarios where lower-privileged users gain unauthorized access to administrative functions. This undermines the confidentiality, integrity, and availability pillars of information security, exposing sensitive organizational data to potential exfiltration or corruption while eroding trust in the platform's reliability among end-users and administrators alike.
To mitigate this risk, immediate remediation is required by upgrading the Advanced Filesystem module to a version later than 1.0.28 where these CSRF protections have been properly implemented according to Drupal core standards. Administrators should also ensure that all dependent modules are updated to maintain compatibility with newer security patches. In environments where an upgrade cannot be performed immediately, temporary mitigations include enforcing strict Content Security Policy headers that restrict form submissions and AJAX requests to same-origin sources only. Additionally, implementing custom validation logic in a separate module or theme layer to verify the presence of valid CSRF tokens before processing any state-changing request can provide a defensive barrier against exploitation. Regular security audits and penetration testing should be conducted to identify similar weaknesses across other modules within the Drupal ecosystem, ensuring comprehensive protection against cross-site request forgery attacks that target session-based authentication mechanisms. This vulnerability is categorized under CWE-352 which defines Cross-Site Request Forgery as a weakness where an attacker causes a user to submit a request they did not intend, and it aligns with ATT&CK technique T1078 regarding Valid Accounts exploitation through social engineering or automated script execution leveraging trusted sessions.