CVE-2017-2578 in Moodle
Summary
by MITRE
In Moodle 3.x, there is XSS in the assignment submission page.
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Analysis
by VulDB Data Team • 05/14/2026
The vulnerability identified as CVE-2017-2578 represents a cross-site scripting flaw discovered in Moodle version 3.x, specifically affecting the assignment submission page functionality. This issue arises from insufficient input validation and output sanitization mechanisms within the platform's assignment handling components. The vulnerability allows malicious users to inject malicious scripts into assignment submission forms, potentially compromising user sessions and enabling unauthorized access to sensitive educational data. The flaw exists in the way Moodle processes and displays user-generated content within assignment submission interfaces, creating an avenue for attackers to execute arbitrary JavaScript code in the context of other users' browsers.
The technical implementation of this vulnerability stems from improper sanitization of user inputs submitted through assignment pages. When users enter text content into assignment submission fields, the system fails to adequately filter or encode special characters that could be interpreted as HTML or JavaScript markup. This weakness is particularly dangerous because assignment submissions often contain rich text content, file names, and descriptive text that may include malicious payloads. The vulnerability manifests when the system renders these submissions back to other users viewing the assignment, executing the injected scripts in their browser context. This type of flaw aligns with CWE-79, which categorizes cross-site scripting vulnerabilities as weaknesses in input validation and output encoding.
The operational impact of CVE-2017-2578 extends beyond simple script execution, potentially enabling attackers to perform session hijacking, steal cookies, redirect users to malicious sites, or access confidential assignment data. In educational environments, this vulnerability could compromise student privacy, academic integrity, and institutional data security. Attackers might exploit the vulnerability to modify assignment grades, access private communications between students and instructors, or gain unauthorized access to the entire Moodle platform. The risk is particularly elevated in environments where multiple users interact with assignment submissions, as the malicious script could affect numerous users simultaneously. This vulnerability directly impacts the CIA triad by threatening confidentiality and integrity of educational data within the learning management system.
Mitigation strategies for CVE-2017-2578 should focus on implementing robust input validation and output encoding mechanisms throughout the Moodle platform. Organizations should ensure that all user-generated content submitted through assignment interfaces undergoes proper sanitization using established security libraries and frameworks. The recommended approach involves implementing Content Security Policy headers to limit script execution, employing proper HTML escaping for all dynamic content, and regularly updating Moodle installations to receive security patches. Security teams should also consider implementing web application firewalls to detect and block suspicious script injection attempts. Additionally, administrative users should conduct regular security audits of assignment-related components and monitor for unusual submission patterns that might indicate exploitation attempts. According to ATT&CK framework, this vulnerability maps to T1059.007 for script injection techniques and T1566 for social engineering through malicious content delivery, emphasizing the need for comprehensive defensive measures across multiple security domains.