Mitigating Stored XSS and DoS Vulnerabilities in Edu-sharing (CVE-2024-28147)

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What is CVE-2024-28147? 

CVE-2024-28147 is a critical security vulnerability that has been identified in the edu-sharing software. The edu-sharing is an open-source e-learning integration solution. The core of the system is a repository for the cooperative creation, management, and usage of objects such as files, links, instances of integrated tools and courses of connected learning management systems such as Moodle. This flaw impacts versions of the software prior to 8.0.8-RC2, 8.1.4-RC0, and 9.0.0-RC19. The vulnerability arises from the software's handling of file uploads through the collection preview images feature, which permits authenticated users to upload arbitrary files. 

Specifically, this issue allows users to upload files such as HTML and SVG files that can contain malicious code. When these files are accessed directly via their URLs, they have the potential to execute malicious JavaScript code. This could lead to unauthorized actions being performed on behalf of users or expose sensitive data. Moreover, the vulnerability can be exploited to launch a Denial of Service (DoS) attack by leveraging complex, nested XML entities within these files. 

The ability to upload and execute arbitrary code poses significant security risks, including potential data breaches and service interruptions. Therefore, it is crucial for users of affected versions to apply the necessary patches and updates to mitigate these vulnerabilities and protect their systems from exploitation. 

The Significance of CVE-2024-28147 CVE-2024-28147 is a critical security vulnerability found in edu-sharing software, affecting versions before 8.0.8-RC2, 8.1.4-RC0, and 9.0.0-RC19. This flaw arises from how the software handles file uploads through the collection preview images feature, allowing authenticated users to upload arbitrary files, including HTML and SVG files with malicious content. 

The implications of this vulnerability are severe. It poses significant risks due to its potential for both stored cross-site scripting (XSS) attacks and Denial of Service (DoS) conditions. Stored XSS vulnerabilities enable attackers to inject malicious scripts that can execute within the context of a user's session, potentially leading to unauthorized data manipulation or theft. Concurrently, the DoS condition could be exploited to cause service disruptions, impacting the availability and reliability of the system. Addressing this vulnerability is crucial to safeguarding the integrity and availability of the edu-sharing system. Users must promptly apply the provided patches to mitigate these risks and ensure the security and stability of their software environments. 

Mitigating the Risk with FortiWeb’s Signature-Based System 

FortiWeb employs a signature-based approach to protect web applications from various threats, including those associated with CVE-2024-28147. This method involves identifying, alerting and blocking known attack patterns using predefined signatures. Here’s a closer look at how FortiWeb’s system effectively counters this specific vulnerability: 

Real-Time Detection of Malicious File Uploads-One of the primary defenses FortiWeb provides is its ability to scrutinize file uploads in real time. The signature-based system includes a comprehensive library of signatures that identify known malicious patterns and payloads. When an authenticated user attempts to upload a file, FortiWeb scans the file content against these signatures. For CVE-2024-28147, this means that files containing malicious HTML or SVG code are detected and blocked before they can be stored or processed by the application. This proactive measure prevents potentially harmful files from being used to exploit the vulnerability. 

Prevention of Malicious Script Execution-Stored XSS attacks, which are a significant risk with CVE-2024-28147, involve the execution of unauthorized JavaScript within a user’s browser. FortiWeb’s signature-based system monitors for patterns indicative of XSS attacks, such as suspicious script content or malformed requests. By filtering out these malicious scripts, FortiWeb ensures that JavaScript cannot execute in user sessions, thereby protecting sensitive data and preventing unauthorized actions. This real-time script execution prevention helps maintain the integrity of the application and protects users from harmful attacks. 

Mitigation of Denial of Service (DoS) Attacks-The vulnerability also has the potential to be exploited for DoS attacks, particularly through the manipulation of nested XML entities in SVG files. FortiWeb’s signature-based system is equipped to identify and block such exploitation attempts by analyzing the structure of incoming data and traffic patterns. By filtering out requests that could cause resource exhaustion or service disruptions, FortiWeb helps ensure that the affected systems remain available and responsive, even under attack. 

Continuous Updates and Adaptation-The cybersecurity landscape is dynamic, with new threats emerging constantly. FortiWeb addresses this challenge by regularly updating its signatures to include new attack patterns and methods. This continuous updating process ensures that FortiWeb remains effective against evolving threats and variants of known vulnerabilities. For CVE-2024-28147, this means that FortiWeb’s protection is not static but adapts to new techniques that attackers might use to exploit the vulnerability. 

Real-Time Monitoring and Alerts-FortiWeb provides real-time monitoring capabilities that are crucial for detecting and responding to potential threats. The system alerts administrators to suspicious activities or attempted exploits, allowing for swift investigation and response. This proactive monitoring ensures that any attempts to exploit CVE-2024-28147 are promptly addressed, reducing the risk of data breaches or service interruptions. 

Finally, it is essential for administrators of edu-sharing systems to mitigate the risk of CVE-2024-28147 by upgrading to the latest software versions that have resolved this vulnerability (versions beyond those previously affected). In addition to updating, enforcing rigorous file validation and sanitization measures on all uploads can help prevent similar vulnerabilities from arising. Implementing a web application firewall like FortiWeb further enhances security by blocking known exploits and offering continuous monitoring and adaptive response to emerging threats. 

Conclusion 

FortiWeb’s signature-based system represents a powerful defense against vulnerabilities like CVE-2024-28147. By effectively detecting and mitigating malicious file uploads and script executions, FortiWeb helps maintain the security and availability of affected systems. Its ability to block known attack patterns, prevent malicious script execution, and mitigate DoS conditions ensures that web applications remain protected from both data breaches and service disruptions. Through continuous updates and real-time monitoring, FortiWeb provides a comprehensive security solution that adapts to the evolving threat landscape, safeguarding digital environments against critical vulnerabilities.