A significant security flaw has been identified in the DotNetNuke (DNN) Platform, a widely utilized content management system (CMS). This vulnerability, designated as CVE-2025-59545, carries a critical severity score of 9.1 out of 10 and affects all DNN Platform versions prior to 10.1.0. The flaw resides in the platform’s Prompt module, allowing attackers to execute malicious scripts by exploiting the way it processes commands that return raw HTML output.
Understanding the Vulnerability
The DNN Platform is renowned for its robust content management capabilities, enabling users to create and manage web content efficiently. Central to its functionality is the Prompt module, designed to execute various commands for administrative tasks. However, a critical oversight in this module’s design has led to a stored cross-site scripting (XSS) vulnerability.
Typically, DNN sanitizes user-submitted data to prevent the execution of unauthorized scripts. This sanitation process ensures that any input displayed on the website does not contain harmful code. However, the Prompt module deviates from this standard practice. It processes command outputs as executable HTML without adequate sanitation, creating an avenue for attackers to inject and execute malicious scripts within the application’s trusted environment.
Potential Risks and Implications
The implications of this vulnerability are profound, especially for organizations operating DNN installations with super-user privileges. Attackers can craft malicious inputs containing embedded scripts or harmful markup. When these inputs are processed through specific Prompt commands, they are rendered directly in browsers without proper security validation. This flaw exposes the system to several risks:
– Data Theft: Malicious scripts can be used to steal sensitive information from users, including login credentials and personal data.
– Session Hijacking: Attackers can hijack user sessions, gaining unauthorized access to user accounts and potentially escalating privileges.
– Website Defacement: Malicious actors can alter the appearance and content of the website, damaging the organization’s reputation.
– Malware Distribution: The vulnerability can be exploited to distribute malware to users visiting the compromised site.
Mechanism of Exploitation
The exploitation of this vulnerability hinges on the fundamental design flaw in how the Prompt module handles command execution and output rendering. When an attacker submits crafted input through the module, the system fails to distinguish between legitimate HTML output and malicious script content. This oversight allows untrusted data to be processed and returned as HTML, effectively bypassing the application’s security boundaries.
The attack vector follows a stored XSS pattern, categorized under CWE-79 (Improper Neutralization of Input During Web Page Generation). Malicious payloads can be persistently stored within the system and executed whenever the compromised content is accessed. This persistence amplifies the vulnerability’s impact, affecting not only the initial victim but potentially all subsequent users who interact with the compromised content.
Discovery and Response
This critical weakness was identified through comprehensive security research conducted by analysts on GitHub. Their findings underscore the importance of continuous platform monitoring for emerging threats. The vulnerability was officially published on September 23, 2025, and has been addressed in DNN Platform version 10.1.0. Organizations using affected versions are strongly advised to upgrade to version 10.1.0 immediately to mitigate this critical security flaw.
Broader Context of DNN Platform Vulnerabilities
The discovery of CVE-2025-59545 is part of a series of vulnerabilities identified in the DNN Platform over recent years. For instance, in May 2025, a remote code execution vulnerability (CVE-2025-48376) was found, allowing malicious SuperUsers to craft requests that utilize external URLs during site export, potentially compromising the platform’s integrity. This issue was addressed in version 9.13.9.
Additionally, in June 2025, a cross-site scripting vulnerability (CVE-2025-52485) was discovered, affecting versions 6.0.0 to 10.0.0. This flaw allowed attackers to inject malicious scripts into the Activity Feed Attachments endpoint, leading to unintended script execution in user feeds. Users were advised to update to version 10.0.1 or later to mitigate this risk.
These incidents highlight the evolving nature of security threats and the necessity for organizations to remain vigilant, ensuring their systems are updated and fortified against potential exploits.
Recommendations for Organizations
To safeguard against the risks associated with CVE-2025-59545 and similar vulnerabilities, organizations should consider the following actions:
1. Immediate Upgrade: Update the DNN Platform to version 10.1.0 or later to patch the identified vulnerability.
2. Regular Security Audits: Conduct periodic security assessments to identify and address potential vulnerabilities proactively.
3. User Training: Educate users and administrators about the risks of XSS attacks and the importance of input validation.
4. Implement Content Security Policy (CSP): Utilize CSP headers to restrict the sources from which scripts can be executed, adding an additional layer of security.
5. Monitor System Logs: Regularly review system logs for unusual activities that may indicate attempted exploits.
By adopting these measures, organizations can enhance their security posture and mitigate the risks associated with this and other vulnerabilities.
Conclusion
The identification of CVE-2025-59545 in the DNN Platform’s Prompt module serves as a critical reminder of the importance of rigorous security practices in web content management systems. Organizations must remain proactive in updating their systems, conducting regular security audits, and educating users to defend against evolving cyber threats.
