CVE-2026-24837 is a cross-site scripting (XSS) vulnerability classified under CWE-79 found in the Dnn.Platform, an open-source web content management system within the Microsoft ecosystem. The vulnerability affects versions starting from 9.0.0 up to but excluding 9.13.10 and 10.2.0. The root cause is improper neutralization of input during web page generation, specifically in the handling of module friendly names. These friendly names can include malicious script code that executes during certain operations in the Persona Bar, a management interface component of Dnn.Platform. The attack vector requires network access with high privileges (authenticated users with elevated rights) and some user interaction. The vulnerability allows an attacker to execute arbitrary scripts in the context of the affected application, potentially leading to full compromise of confidentiality, integrity, and availability of the system. The CVSS v3.1 base score is 7.7, reflecting a high severity level due to the critical impact on data and system control, combined with the requirement for high privileges and user interaction. Although no known exploits are currently reported in the wild, the vulnerability poses a significant risk to organizations using affected versions of Dnn.Platform. The issue is resolved in versions 9.13.10 and 10.2.0, which include fixes that properly sanitize module friendly names to prevent script injection. Organizations running vulnerable versions should prioritize patching to mitigate potential exploitation.

For European organizations, this vulnerability could lead to severe consequences including unauthorized disclosure of sensitive information, manipulation or destruction of data, and disruption of web services hosted on Dnn.Platform. Since the vulnerability allows script execution in the context of the CMS, attackers could hijack user sessions, steal credentials, or perform actions on behalf of legitimate users, especially those with administrative privileges. This could result in data breaches, defacement of websites, or pivoting to other internal systems. Organizations relying on Dnn.Platform for public-facing websites or internal portals are particularly at risk. The requirement for high privileges and user interaction somewhat limits the attack surface but does not eliminate the threat, especially in environments with many administrators or editors. The lack of known exploits in the wild reduces immediate risk but does not preclude targeted attacks or future exploit development. The vulnerability's impact on confidentiality, integrity, and availability makes it critical for organizations to address promptly.

1. Upgrade affected Dnn.Platform instances to version 9.13.10 or 10.2.0 or later, where the vulnerability is fixed. 2. Restrict high-privilege user accounts to trusted personnel and enforce strong authentication mechanisms to reduce the risk of credential compromise. 3. Implement strict input validation and sanitization policies for module friendly names and other user-supplied inputs within the CMS, even beyond the provided patches. 4. Monitor logs and user activities in the Persona Bar for unusual behavior indicative of attempted exploitation. 5. Employ Content Security Policy (CSP) headers to limit the impact of potential XSS attacks by restricting script execution sources. 6. Conduct regular security audits and penetration testing focused on CMS components to detect similar vulnerabilities. 7. Educate administrators and content managers about the risks of injecting scripts or untrusted content into module names or other CMS fields. 8. Isolate the CMS environment and limit network exposure where possible to reduce attack surface.