CVE-2012-6104 in Moodle
Summary
by MITRE
blog/rsslib.php in Moodle 2.2.x before 2.2.7, 2.3.x before 2.3.4, and 2.4.x before 2.4.1 allows remote attackers to obtain sensitive information from site-level blogs by leveraging the guest role and reading an RSS feed.
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Analysis
by VulDB Data Team • 02/25/2019
The vulnerability identified as CVE-2012-6104 affects Moodle versions prior to specific patch releases, creating a significant information disclosure risk through improperly controlled access to blog feeds. This flaw resides in the blog/rsslib.php component of the learning management system, where guest users can exploit the system's RSS feed functionality to access sensitive blog content that should remain restricted to authenticated users. The vulnerability represents a classic case of insufficient access control mechanisms, where the system fails to properly verify user permissions before serving content through the RSS feed interface.
The technical implementation of this vulnerability stems from inadequate authorization checks within the RSS feed generation logic. When guest users attempt to access blog feeds through the RSS interface, the system does not properly validate whether the requesting user has appropriate permissions to view the specific blog content. This allows unauthorized access to site-level blog posts that contain sensitive information, potentially exposing educational content, user discussions, or institutional data that should only be accessible to registered users with proper enrollment status. The flaw operates at the application logic level and manifests as a privilege escalation issue through the RSS feed interface.
From an operational perspective, this vulnerability creates serious security implications for educational institutions using affected Moodle versions. Attackers can exploit this weakness to gather intelligence about course content, student activities, faculty discussions, or institutional communications without requiring valid credentials. The impact extends beyond simple information disclosure as it may enable further attacks through the acquisition of sensitive metadata or the identification of vulnerable components within the system. This vulnerability aligns with CWE-284 which addresses improper access control issues, and could potentially support techniques described in the ATT&CK framework under privilege escalation and information gathering tactics.
Organizations using affected Moodle versions should immediately implement the available patches that address this specific access control flaw in the RSS feed functionality. The recommended mitigation involves updating to Moodle versions 2.2.7, 2.3.4, or 2.4.1, which contain the necessary fixes for the authorization checks in blog/rsslib.php. Additionally, system administrators should review and tighten access controls for blog features, particularly regarding guest user permissions, and consider implementing network-level restrictions to limit access to RSS feed endpoints. Security monitoring should be enhanced to detect unusual access patterns to blog feed URLs, and regular security assessments should verify that access control mechanisms function properly across all content delivery interfaces.