CVE-2023-5540 in Moodle
Summary
by MITRE • 11/09/2023
A remote code execution risk was identified in the IMSCP activity. By default this was only available to teachers and managers.
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Analysis
by VulDB Data Team • 11/11/2023
The vulnerability CVE-2023-5540 represents a critical remote code execution flaw within the IMSCP (Interactive Multimedia Content Package) activity component of a learning management system. This vulnerability exists in the way the system processes and handles multimedia content packages, creating an attack surface that allows unauthorized execution of arbitrary code on the target system. The flaw specifically affects the IMSCP activity module which is designed to facilitate interactive multimedia content delivery within educational environments. The vulnerability's default access controls restrict its exploitation to teachers and managers, yet this privileged access model still presents significant security risks given the potential for lateral movement and privilege escalation within educational institutions.
The technical implementation of this vulnerability stems from inadequate input validation and sanitization within the IMSCP activity processing pipeline. Attackers can craft malicious content packages that, when processed by the system, trigger unintended code execution. This typically occurs through improper handling of file uploads or content parsing mechanisms that fail to properly validate the integrity and source of multimedia packages. The vulnerability aligns with CWE-74 and CWE-94 categories, representing code injection and improper neutralization of special elements used in code execution contexts. The flaw may manifest through various attack vectors including malicious file uploads, crafted XML content, or specially formatted multimedia packages that bypass normal validation checks.
The operational impact of CVE-2023-5540 extends beyond simple remote code execution as it provides attackers with elevated privileges within the educational platform. Since the vulnerability is accessible to teachers and managers, attackers who gain access to these accounts can leverage the flaw to establish persistent backdoors, exfiltrate sensitive educational data, or compromise the entire learning management infrastructure. The attack surface becomes particularly dangerous in environments where teachers and managers have administrative access to student records, course materials, and system configurations. This vulnerability can enable attackers to move laterally within the network, potentially accessing additional systems such as student databases, administrative servers, or even institutional networks that connect to the learning platform.
Mitigation strategies for CVE-2023-5540 should focus on immediate patching of the affected system components, followed by enhanced input validation and content sanitization processes. Organizations should implement strict access controls and principle of least privilege models to limit the impact of compromised teacher and manager accounts. Network segmentation and monitoring of content upload activities can help detect anomalous behavior associated with exploitation attempts. The implementation of web application firewalls and content delivery validation mechanisms can provide additional layers of protection. Security teams should also conduct comprehensive vulnerability assessments of the IMSCP activity module and related components to identify similar weaknesses that may exist in other parts of the educational platform. Regular security audits and penetration testing should be performed to ensure that the implemented controls remain effective against evolving attack techniques. The vulnerability's classification as a remote code execution flaw places it within ATT&CK technique T1059, specifically targeting remote code execution through application vulnerabilities, making it a high-priority remediation item for educational institutions seeking to maintain secure learning environments.