CVE-2025-9567 is a Reflected Cross-site Scripting (XSS) vulnerability identified in the Sunnet eHRD CTMS (Clinical Trial Management System). This vulnerability arises from improper neutralization of input during web page generation, classified under CWE-79. Specifically, the system fails to adequately sanitize user-supplied input before reflecting it back in web responses, allowing unauthenticated remote attackers to inject and execute arbitrary JavaScript code in the browsers of users who visit a crafted URL. The attack vector is network-based (AV:N), requires no privileges (PR:N), and no authentication (AT:N), but does require user interaction (UI:A), typically through phishing or social engineering to lure victims to malicious links. The vulnerability has a CVSS 4.0 base score of 5.1 (medium severity), reflecting limited impact on confidentiality, integrity, and availability, but with a low attack complexity and no need for authentication. Exploitation could lead to session hijacking, credential theft, or unauthorized actions performed in the context of the victim's session within the eHRD CTMS application. Although no known exploits are currently reported in the wild, the vulnerability poses a tangible risk, especially in environments where users access the affected system frequently. The affected product, Sunnet eHRD CTMS, is used for managing clinical trial data, which often contains sensitive patient and research information, increasing the potential impact of successful exploitation.

For European organizations, especially those involved in clinical research, pharmaceutical development, or healthcare services utilizing the Sunnet eHRD CTMS, this vulnerability could lead to significant risks. Exploitation may result in unauthorized access to sensitive clinical trial data, manipulation of trial records, or leakage of personally identifiable information (PII) and protected health information (PHI). Such breaches could undermine patient privacy, violate GDPR regulations, and damage organizational reputation. Additionally, attackers could leverage the XSS vulnerability to conduct further attacks such as delivering malware, redirecting users to malicious sites, or performing actions on behalf of legitimate users, potentially disrupting clinical trial operations. Given the critical nature of clinical trial data integrity and confidentiality, even a medium severity vulnerability warrants prompt attention. The phishing vector also means that user awareness and training are crucial, as attackers rely on social engineering to trigger the exploit.

To mitigate this vulnerability, European organizations should implement the following specific measures: 1) Apply patches or updates from Sunnet as soon as they become available; currently, no patch links are provided, so organizations should engage with the vendor for remediation timelines. 2) Employ robust input validation and output encoding on all user-supplied data within the eHRD CTMS to prevent script injection, including the use of Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts. 3) Enhance email and web filtering to detect and block phishing attempts that could deliver malicious URLs exploiting this XSS flaw. 4) Conduct targeted user awareness training focusing on recognizing phishing and suspicious links, especially for users with access to the eHRD CTMS. 5) Monitor web application logs and user activity for unusual patterns indicative of exploitation attempts. 6) Consider deploying Web Application Firewalls (WAFs) with rules tuned to detect and block reflected XSS payloads targeting the eHRD CTMS. 7) Limit the exposure of the eHRD CTMS to only necessary users and networks, employing network segmentation and access controls to reduce the attack surface.