CVE-2015-6253 in edx-platform
Summary
by MITRE
edx-platform before 2015-08-17 allows XSS in the Studio listing of courses.
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Analysis
by VulDB Data Team • 07/15/2020
The vulnerability identified as CVE-2015-6253 affects the edx-platform learning management system prior to the 2015-08-17 release, specifically targeting the Studio component which serves as the course creation and management interface. This issue represents a cross-site scripting vulnerability that enables malicious actors to inject arbitrary web scripts into course listings, potentially compromising the security of the entire platform and its users. The vulnerability resides within the Studio's course listing functionality, where user-supplied input is not properly sanitized or validated before being rendered in the web interface.
The technical flaw stems from insufficient input validation and output encoding mechanisms within the edx-platform's Studio module. When administrators or instructors create or modify course listings, the system fails to adequately sanitize user-provided data before displaying it in the course catalog interface. This allows attackers to submit malicious script code within course titles, descriptions, or other editable fields, which then executes in the context of other users' browsers when they view the course listings. The vulnerability is classified as CWE-79 - Cross-site Scripting, specifically representing a stored XSS variant where malicious payloads persist in the application's database and are executed each time the affected content is displayed.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable sophisticated attack vectors including session hijacking, credential theft, and redirection to malicious sites. An attacker who successfully exploits this vulnerability could gain unauthorized access to user sessions, potentially compromising the integrity of course data and student information. The attack surface is particularly concerning given that the Studio interface is typically accessed by trusted administrators and instructors who may have elevated privileges within the platform. This vulnerability could be exploited to escalate privileges or gain access to sensitive course materials, potentially affecting thousands of users across multiple institutions utilizing the edx-platform.
Mitigation strategies for CVE-2015-6253 involve implementing comprehensive input sanitization and output encoding measures throughout the platform's data handling processes. Organizations should ensure that all user-provided content is properly escaped before rendering in web interfaces, with particular attention to the Studio's course listing functionality. The recommended approach includes implementing Content Security Policy headers to prevent unauthorized script execution, conducting regular security audits of input validation mechanisms, and applying the patched version of edx-platform released on or after 2015-08-17. Additionally, security controls should be implemented to restrict user permissions within the Studio interface, limiting the ability of potentially compromised accounts to inject malicious content. This vulnerability aligns with ATT&CK technique T1059.007 - Command and Scripting Interpreter: JavaScript, demonstrating how XSS vulnerabilities can be leveraged to execute malicious code in victim browsers. Organizations should also consider implementing web application firewalls and monitoring for suspicious script injection patterns to detect potential exploitation attempts.