CVE-2025-53516 is a reflected cross-site scripting (XSS) vulnerability identified in MedDream PACS Premium version 7.3.6.870, specifically within the downloadZip functionality. Reflected XSS occurs when malicious input is immediately returned by a web application without proper sanitization or encoding, allowing attackers to inject and execute arbitrary JavaScript code in the victim's browser. In this case, an attacker can craft a specially designed URL that, when accessed by a user, triggers the execution of malicious scripts. This can lead to theft of session cookies, user impersonation, or redirection to malicious sites, compromising confidentiality and integrity of user data. The vulnerability does not require authentication (AV:N) but does require user interaction (UI:R), such as clicking the malicious link. The scope is considered changed (S:C) because the vulnerability can affect resources beyond the vulnerable component, potentially impacting the entire user session. The CVSS 3.1 base score is 6.1, indicating medium severity with low complexity (AC:L) and no impact on availability (A:N). No known exploits have been reported in the wild, and no official patches have been released as of the publication date. The vulnerability is classified under CWE-79, which is a common web application security weakness involving improper neutralization of input during web page generation. MedDream PACS Premium is a medical imaging software widely used in healthcare environments for managing and viewing medical images, making the confidentiality and integrity of data critical. The reflected XSS vulnerability could be exploited via phishing or social engineering to compromise user sessions or steal sensitive information.

For European organizations, particularly healthcare providers using MedDream PACS Premium 7.3.6.870, this vulnerability poses a moderate risk. Successful exploitation can lead to unauthorized disclosure of sensitive patient information through session hijacking or credential theft, undermining patient privacy and violating GDPR requirements. Integrity of user sessions can be compromised, potentially allowing attackers to perform unauthorized actions within the application. Although availability is not impacted, the breach of confidentiality and integrity can damage organizational reputation and lead to regulatory penalties. The requirement for user interaction means phishing campaigns or targeted social engineering are likely attack vectors. Given the critical nature of healthcare data and the reliance on PACS systems for diagnostics, even a medium-severity vulnerability can have significant operational and compliance consequences. European healthcare institutions with less mature cybersecurity awareness or lacking web filtering controls are particularly vulnerable. Additionally, the cross-site scripting flaw could be leveraged as a stepping stone for more complex attacks within the network.

1. Restrict access to the downloadZip functionality to trusted users and networks only, using network segmentation and access control lists. 2. Deploy and configure Web Application Firewalls (WAFs) with rules to detect and block reflected XSS payloads targeting the vulnerable endpoint. 3. Educate users, especially healthcare staff, about the risks of clicking on unsolicited or suspicious links, emphasizing phishing awareness. 4. Implement Content Security Policy (CSP) headers to limit the execution of unauthorized scripts in browsers accessing the PACS system. 5. Monitor web server logs for unusual or suspicious URL requests that may indicate exploitation attempts. 6. Engage with MedDream support to obtain patches or updates addressing this vulnerability as soon as they become available. 7. Consider deploying browser isolation or endpoint protection solutions that can mitigate the impact of malicious scripts. 8. Conduct regular security assessments and penetration testing focused on web application vulnerabilities in the PACS environment. 9. Ensure all other software components and dependencies are up to date to reduce the attack surface. 10. Implement multi-factor authentication to reduce the impact of stolen credentials if session hijacking occurs.