CVE-2019-14829 in Moodle
Summary
by MITRE • 03/20/2021
A vulnerability was found in Moodle affection 3.7 to 3.7.1, 3.6 to 3.6.5, 3.5 to 3.5.7 and earlier unsupported versions where activity creation capabilities were not correctly respected when selecting the activity to use for a course in single activity mode.
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Analysis
by VulDB Data Team • 09/08/2025
This vulnerability exists in Moodle versions 3.7 through 3.7.1, 3.6 through 3.6.5, 3.5 through 3.5.7, and earlier unsupported versions. The flaw represents a critical access control issue that undermines the core security model of the learning management system. The vulnerability specifically affects the course configuration functionality where Moodle allows instructors to set courses to single activity mode, which restricts the course content to a single activity type. When users with limited permissions attempt to create or modify activities within this single activity mode context, the system fails to properly validate their capabilities and permissions. This misconfiguration allows unauthorized users to bypass intended access controls and potentially perform actions they should not be permitted to execute.
The technical implementation flaw stems from insufficient capability checking within the activity selection and creation process. In single activity mode, Moodle should strictly enforce the permissions of the user attempting to modify course activities, ensuring that only users with appropriate capabilities can select or create specific activity types. However, the vulnerability allows users with restricted permissions to manipulate the activity selection process, potentially enabling them to add activities that should be restricted to higher-privilege users. This represents a classic privilege escalation vulnerability where the system fails to properly validate user permissions at critical decision points in the activity creation workflow. The flaw aligns with CWE-285, which addresses improper authorization in software systems, and specifically demonstrates weaknesses in access control mechanisms that should enforce least privilege principles.
The operational impact of this vulnerability extends beyond simple permission bypass to potentially compromise the integrity and security of entire course environments. Attackers could exploit this vulnerability to inject malicious activities into courses, modify existing activities in unauthorized ways, or gain access to course content that should remain restricted. In educational environments, this could lead to unauthorized content modification, data exposure, or even the complete subversion of course integrity. The vulnerability affects the fundamental course management capabilities of Moodle, potentially allowing attackers to manipulate learning experiences and access sensitive educational data. Organizations using Moodle in production environments face significant risk if this vulnerability is exploited, as it could enable attackers to undermine the trust and security model that educational institutions rely upon for their digital learning platforms.
Organizations should immediately implement mitigations that include updating to patched versions of Moodle where available, implementing additional access controls through custom code modifications, and conducting comprehensive audits of user permissions within course environments. The recommended approach includes ensuring that all users with capabilities to modify course activities are properly validated against their intended permissions, particularly in single activity mode contexts. Security administrators should also consider implementing monitoring and logging of activity creation and modification events to detect potential exploitation attempts. This vulnerability highlights the importance of proper capability validation in complex educational platforms and demonstrates how seemingly minor access control oversights can have significant security implications. The remediation efforts should align with ATT&CK framework techniques related to privilege escalation and defense evasion, ensuring that organizations maintain robust security postures against such exploitation vectors.