CVE-2016-5012 in Moodle
Summary
by MITRE
In Moodle 3.x, glossary search displays entries without checking user permissions to view them.
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Analysis
by VulDB Data Team • 05/14/2026
The vulnerability described in CVE-2016-5012 represents a critical access control flaw within the Moodle learning management system affecting versions 3.x. This issue stems from improper authorization checks during glossary search operations, where the system fails to validate whether authenticated users possess adequate permissions to view specific glossary entries. The flaw exists in the core glossary module implementation, which is a fundamental component used across educational institutions for organizing and displaying terminology and definitions within course content.
The technical nature of this vulnerability aligns with CWE-285, which addresses insufficient authorization checks in software systems. When users perform search operations within glossary components, the system returns results without verifying that the requesting user has been granted appropriate access rights to view each individual entry. This oversight creates a privilege escalation scenario where users may inadvertently gain access to restricted glossary content that should only be visible to specific roles such as instructors, administrators, or enrolled students with particular permissions. The vulnerability operates at the application logic level, specifically within the search and retrieval mechanisms of the glossary feature.
From an operational impact perspective, this vulnerability compromises the confidentiality and integrity of educational content within Moodle environments. Attackers or unauthorized users could potentially access sensitive course materials, proprietary definitions, or private glossary entries that contain information not intended for general viewing. This breach affects the principle of least privilege, as users might access content beyond their designated access levels. The vulnerability is particularly concerning in academic settings where glossaries may contain draft course materials, assessment information, or content that should remain restricted to specific user groups. The impact extends to data privacy compliance issues, especially in environments subject to educational privacy regulations.
The mitigation strategies for this vulnerability should focus on implementing proper access control checks within the glossary search functionality. System administrators should ensure that all glossary search operations include permission validation before displaying results to users. This involves modifying the search logic to verify user roles and permissions against each glossary entry before inclusion in search results. The fix should align with ATT&CK technique T1078 which addresses valid accounts and privilege escalation. Organizations should also consider implementing regular security audits of core Moodle components and maintaining updated security patches. Additionally, access control policies should be reviewed and enforced consistently across all course modules to prevent similar issues in other components. The vulnerability highlights the importance of comprehensive security testing, particularly for features that handle user-generated content and search capabilities, ensuring that all data retrieval operations maintain proper authorization controls.