CVE-2025-41043 is a stored Cross-Site Scripting (XSS) vulnerability identified in appRain CMF version 4.0.5, a content management framework. The vulnerability arises from improper neutralization of user input during web page generation, specifically within the parameters 'data[AppReportCode][id]' and 'data[AppReportCode][name]' in the /apprain/appreport/manage/ endpoint. Because these parameters are not properly validated or sanitized, an authenticated user can inject malicious scripts that are stored on the server and later executed in the browsers of users who access the affected pages. This stored XSS does not require user interaction beyond visiting the compromised page, and the vulnerability can be exploited remotely over the network without elevated privileges but does require the attacker to have authenticated access to the application. The CVSS 4.0 base score is 5.1 (medium severity), reflecting the network attack vector, low attack complexity, no privileges required beyond authentication, and no user interaction needed for exploitation. The vulnerability impacts confidentiality, integrity, and availability to a limited extent by enabling script execution in victim browsers, potentially leading to session hijacking, defacement, or unauthorized actions within the context of the authenticated user. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability was reserved in April 2025 and published in September 2025 by INCIBE, indicating recent discovery and disclosure.

For European organizations using appRain CMF 4.0.5, this vulnerability poses a moderate risk. Stored XSS can lead to session hijacking, credential theft, unauthorized actions, or malware distribution within the affected web application. Since exploitation requires authentication, the threat is primarily from malicious insiders or compromised user accounts. However, once exploited, attackers can escalate their privileges or move laterally within the organization’s web infrastructure. This can result in data breaches, reputational damage, and compliance violations under GDPR if personal data is exposed or manipulated. The impact is heightened for organizations relying on appRain CMF for critical web services or internal portals, especially in sectors like finance, healthcare, or government where data sensitivity is high. Additionally, the lack of patches increases the window of exposure. European organizations must be vigilant due to stringent data protection regulations and the potential for regulatory penalties if vulnerabilities lead to data compromise.

Specific mitigation steps include: 1) Immediate review and sanitization of all user inputs, particularly the 'data[AppReportCode][id]' and 'data[AppReportCode][name]' parameters, using context-appropriate encoding to neutralize malicious scripts. 2) Implement Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts and reduce the impact of XSS. 3) Enforce strict authentication and session management controls to limit the risk from compromised accounts. 4) Conduct thorough code audits and penetration testing focused on input validation and output encoding in the appRain CMF environment. 5) Monitor application logs for unusual activities or injection attempts targeting the vulnerable endpoints. 6) Segregate the affected application environment to limit lateral movement if exploitation occurs. 7) Engage with the vendor or community to obtain patches or updates as soon as they become available. 8) Educate users about phishing and social engineering risks to reduce the likelihood of credential compromise that could enable exploitation.