CVE-2015-3404 in Certify Module
Summary
by MITRE
The Certify module before 6.x-2.3 for Drupal does not properly perform node access checks, which allows remote authenticated users to bypass intended access restrictions and obtain sensitive PDF certificate information via vectors related to "showing (and creating) the PDF certificates."
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Analysis
by VulDB Data Team • 03/19/2019
The Certify module for Drupal versions prior to 6.x-2.3 contains a critical access control vulnerability that undermines the platform's security model. This flaw exists within the node access checking mechanism, which is fundamental to Drupal's permission system that governs user access to content. The vulnerability specifically affects the module's handling of PDF certificate generation and display operations, creating a pathway for authenticated attackers to circumvent intended access controls.
The technical implementation flaw stems from insufficient validation of user permissions during PDF certificate operations. When users attempt to view or generate PDF certificates, the module fails to properly verify whether the requesting user possesses adequate privileges to access the target node. This weakness allows attackers to manipulate the system into revealing sensitive certificate information that should be restricted to authorized personnel only. The vulnerability is particularly concerning because it operates at the node access layer, meaning it can potentially expose any certificate content regardless of the typical access control restrictions.
Operationally, this vulnerability enables authenticated users to escalate their privileges within the system by accessing PDF certificates that contain sensitive information. Attackers can exploit this flaw to obtain confidential data such as personal identification details, certification records, or other protected information that would normally be restricted. The impact extends beyond simple information disclosure as it can facilitate further attacks by providing attackers with valuable data about system users and their credentials. This type of vulnerability directly violates the principle of least privilege that is central to secure system design and can lead to cascading security issues.
The vulnerability aligns with CWE-284, which addresses improper access control, and represents a classic example of insufficient authorization checks in web applications. From an attack framework perspective, this flaw maps to ATT&CK technique T1078 which covers valid accounts and privilege escalation. Organizations using the Certify module should implement immediate mitigations including upgrading to version 6.x-2.3 or later, which contains the necessary access control fixes. Additionally, administrators should review and tighten access controls for certificate-related content, implement additional monitoring for PDF generation activities, and consider temporary workarounds such as disabling certificate generation for non-privileged users until the upgrade is complete. The vulnerability demonstrates the critical importance of proper access control implementation in content management systems and highlights the need for thorough security testing of third-party modules before deployment.