CVE-2012-1156 in Moodle
Summary
by MITRE
Moodle before 2.2.2 has users' private files included in course backups
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Analysis
by VulDB Data Team • 11/15/2019
The vulnerability described in CVE-2012-1156 represents a critical security flaw in Moodle learning management systems prior to version 2.2.2 where user private files were inadvertently included in course backup archives. This issue stems from inadequate access control mechanisms during the backup process, allowing unauthorized users to gain access to sensitive personal data that should remain restricted to individual users. The flaw exists within the backup and restore functionality of Moodle, which is a core component of the platform's architecture designed to preserve course content and user progress. When administrators or users with appropriate privileges create course backups, the system fails to properly filter out private user files that are associated with courses but should remain protected within individual user spaces. This vulnerability directly impacts the principle of least privilege and data confidentiality, as it violates the expected boundaries between user privacy and course content management.
The technical implementation of this flaw occurs within Moodle's backup engine where the system does not properly distinguish between course-specific files that are intended for sharing and user-private files that should remain confidential. The backup process aggregates various file types including uploaded documents, personal submissions, and user-specific content without adequate filtering mechanisms. This creates a scenario where private files such as assignment submissions, personal notes, and user-generated content that should only be accessible to the respective user or course instructors become exposed within backup archives. The vulnerability is classified as a data exposure issue that allows for unauthorized information disclosure, potentially violating data protection regulations and privacy standards. From a cybersecurity perspective, this represents a failure in data access control and information flow management, where the system does not properly enforce user access boundaries during backup operations.
The operational impact of this vulnerability is substantial for educational institutions relying on Moodle for their learning management needs. Course backups containing private user files could be inadvertently shared with unauthorized individuals, including other students, external auditors, or system administrators who do not require access to such sensitive information. This exposure creates potential risks for student privacy, academic integrity, and institutional compliance with data protection regulations such as GDPR or FERPA. The vulnerability becomes particularly concerning when backups are stored in shared locations or transmitted across networks without proper encryption or access controls. Organizations may face regulatory penalties, loss of trust from users, and potential legal consequences if private educational data is compromised through this vulnerability. The impact extends beyond simple data exposure as it undermines the fundamental security model of the learning management system.
Mitigation strategies for CVE-2012-1156 involve immediate upgrade to Moodle version 2.2.2 or later, which includes fixed backup mechanisms that properly separate private user files from course content. Organizations should also implement additional access controls around backup operations, ensuring that only authorized personnel can create or access backup archives. Regular security audits of backup processes and file permissions should be conducted to prevent similar issues. The vulnerability aligns with CWE-200 (Information Exposure) and CWE-284 (Improper Access Control) categories, representing failures in proper data access management and information disclosure controls. From an ATT&CK framework perspective, this vulnerability maps to T1070 (Indicator Removal on Host) and T1566 (Phishing) as attackers could potentially use exposed private files for social engineering attacks or to gather intelligence about users. Organizations should also consider implementing automated backup monitoring and access logging to detect unauthorized backup activities and ensure proper segregation of private user data from course content.