CVE-2015-5335 in Moodle
Summary
by MITRE
Cross-site request forgery (CSRF) vulnerability in admin/registration/register.php in Moodle through 2.6.11, 2.7.x before 2.7.11, 2.8.x before 2.8.9, and 2.9.x before 2.9.3 allows remote attackers to hijack the authentication of administrators for requests that send statistics to an arbitrary hub URL.
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Analysis
by VulDB Data Team • 07/08/2022
The CVE-2015-5335 vulnerability represents a critical cross-site request forgery flaw within the Moodle learning management system that affects multiple version branches including 2.6.11, 2.7.11, 2.8.9, and 2.9.3. This vulnerability resides in the admin/registration/register.php file and operates as a sophisticated attack vector that enables remote adversaries to manipulate administrative sessions through forged requests. The flaw specifically targets the registration and statistics submission functionality, creating a pathway for unauthorized actors to exploit administrative privileges and potentially gain control over critical system operations. The vulnerability falls under the CWE-352 category of Cross-Site Request Forgery, which is classified as a fundamental web application security weakness that has been consistently documented in industry security frameworks and represents one of the most prevalent attack patterns identified by the OWASP Top Ten project.
The technical implementation of this CSRF vulnerability exploits the absence of proper anti-forgery tokens or validation mechanisms within the registration process that handles statistical data submission to external hub URLs. When administrators navigate to the registration page or perform actions related to statistics collection, the system fails to validate that requests originate from legitimate sources within the same session context. Attackers can craft malicious web pages or exploit existing vulnerabilities in other parts of the system to automatically submit forged requests that appear to come from authenticated administrators. This allows them to manipulate the system's statistical reporting functionality, potentially redirecting data to attacker-controlled endpoints or altering the configuration of statistical submissions without requiring administrative credentials. The vulnerability specifically impacts the hub URL configuration where Moodle sends anonymous usage statistics, creating a potential attack surface that could be leveraged for more sophisticated operations beyond simple data manipulation.
The operational impact of this vulnerability extends far beyond simple statistical data manipulation, as it provides attackers with a method to hijack administrative sessions and potentially escalate privileges within the Moodle environment. Successful exploitation could enable attackers to modify system configurations, manipulate user accounts, or even gain deeper access to the underlying server infrastructure. The statistics submission functionality serves as a potential reconnaissance vector, as attackers could use it to gather information about the target environment or redirect sensitive data to malicious endpoints. This vulnerability particularly affects organizations that rely heavily on Moodle for educational administration, as administrators with elevated privileges are the primary targets for such attacks. The attack requires minimal technical expertise and can be executed through standard web application exploitation techniques, making it particularly dangerous in environments where administrators frequently interact with web-based management interfaces.
Mitigation strategies for CVE-2015-5335 should focus on immediate patch application to the affected Moodle versions, with administrators prioritizing updates to the latest stable releases that contain the necessary CSRF protection mechanisms. The vulnerability demonstrates the critical importance of implementing proper anti-forgery token validation in all web application forms and administrative interfaces, a principle that aligns with the OWASP Top Ten security controls and ATT&CK framework techniques related to privilege escalation and credential access. Organizations should also implement network-level protections including web application firewalls that can detect and block suspicious requests to registration endpoints, while establishing monitoring procedures to identify unusual statistical submission patterns. Security teams should conduct comprehensive vulnerability assessments of their Moodle installations to identify other potential CSRF vulnerabilities in related components, and implement proper session management controls that enforce strict validation of request sources and origins. The remediation process should also include user education regarding the risks of visiting untrusted websites while logged into administrative interfaces, as this vulnerability can be exploited through social engineering or drive-by attacks that leverage the browser's automatic credential handling capabilities.