CVE-2025-55071: MedDream PACS Premium XSS Vulnerability

CVE-2025-55071 Overview

A reflected cross-site scripting (XSS) vulnerability exists in the modifyAnonymize functionality of MedDream PACS Premium 7.3.6.870. This vulnerability allows attackers to execute arbitrary JavaScript code in the context of a victim's browser session by crafting a malicious URL. When a user clicks on the specially crafted link, the malicious script executes with the privileges of the authenticated user, potentially leading to session hijacking, credential theft, or unauthorized actions within the PACS system.

Critical Impact

Healthcare environments using MedDream PACS Premium are at risk of session hijacking and unauthorized access to sensitive medical imaging data through malicious URL exploitation.

Affected Products

• MedDream PACS Premium 7.3.6.870
• MedDream PACS Premium (versions prior to patched release)

Discovery Timeline

• 2026-01-20 - CVE-2025-55071 published to NVD
• 2026-01-20 - Last updated in NVD database

Technical Details for CVE-2025-55071

Vulnerability Analysis

This reflected XSS vulnerability (CWE-79) occurs within the modifyAnonymize functionality of MedDream PACS Premium, a medical imaging system used in healthcare environments. The vulnerability arises from insufficient input validation and output encoding when processing user-supplied data through URL parameters.

When a user accesses a maliciously crafted URL targeting the modifyAnonymize endpoint, the application reflects untrusted input back to the browser without proper sanitization. This allows an attacker to inject arbitrary JavaScript code that executes within the security context of the victim's browser session. In a healthcare environment, this is particularly concerning as it could lead to unauthorized access to protected health information (PHI) and medical imaging data.

The attack requires user interaction—specifically, the victim must click on or navigate to the attacker-controlled URL. Once executed, the malicious script can access session cookies, perform actions on behalf of the authenticated user, redirect users to phishing sites, or exfiltrate sensitive medical data displayed within the PACS interface.

Root Cause

The root cause of this vulnerability is improper input validation and lack of output encoding in the modifyAnonymize functionality. User-supplied input from URL parameters is directly reflected in the HTTP response without proper sanitization or contextual output encoding, allowing JavaScript code to be executed in the victim's browser. This represents a failure to implement proper input validation on the server side and appropriate output encoding when rendering dynamic content.

Attack Vector

The attack vector is network-based and requires user interaction. An attacker crafts a malicious URL containing JavaScript payload targeting the vulnerable modifyAnonymize endpoint. The attacker then distributes this URL through phishing emails, social engineering, or by embedding it in malicious web pages. When an authenticated MedDream PACS user clicks the link, the malicious JavaScript executes in their browser session, potentially allowing the attacker to steal session tokens, access medical imaging data, or perform unauthorized actions within the PACS system.

The vulnerability is particularly dangerous in healthcare settings where users may receive numerous legitimate links related to patient care and imaging studies, making them more susceptible to clicking on malicious URLs that appear to reference the PACS system.

Detection Methods for CVE-2025-55071

Indicators of Compromise

• Unusual URL patterns in web server logs containing JavaScript code or encoded script tags targeting the modifyAnonymize endpoint
• HTTP requests with URL parameters containing common XSS payloads such as <script>, javascript:, or encoded variants
• Unexpected outbound connections from user browsers during PACS sessions
• Session anomalies or account access from unexpected IP addresses following suspicious URL access

Detection Strategies

• Deploy web application firewalls (WAF) with rules to detect and block common XSS payloads in URL parameters
• Implement Content Security Policy (CSP) headers to restrict script execution sources and detect policy violations
• Enable detailed logging for the modifyAnonymize endpoint and monitor for suspicious input patterns
• Use browser-based XSS auditors and security extensions that can detect reflected script injection attempts

Monitoring Recommendations

• Monitor web application logs for requests to the modifyAnonymize endpoint containing URL-encoded special characters or script tags
• Configure SIEM alerts for patterns indicative of XSS exploitation attempts against MedDream PACS
• Track session token usage patterns to identify potential session hijacking following XSS attacks
• Review referrer headers in logs to identify external sources directing users to suspicious PACS URLs

How to Mitigate CVE-2025-55071

Immediate Actions Required

• Review and apply any security updates from MedDream for PACS Premium addressing this vulnerability
• Implement Content Security Policy (CSP) headers to restrict inline script execution and mitigate XSS impact
• Deploy or update web application firewall rules to filter XSS payloads targeting the modifyAnonymize functionality
• Educate users about phishing risks and the importance of verifying URLs before clicking, especially those referencing the PACS system

Patch Information

Organizations should consult the Talos Intelligence Vulnerability Report for the latest information on vendor patches and remediation guidance. Contact MedDream support to obtain the security patch addressing this vulnerability and verify that the installed version includes the fix for CVE-2025-55071.

Workarounds

• Implement strict Content Security Policy headers that disallow inline scripts and restrict script sources to trusted domains
• Configure web application firewalls to inspect and sanitize URL parameters for the modifyAnonymize endpoint
• Restrict access to the MedDream PACS interface to trusted network segments and authenticated users only
• Consider implementing URL filtering at the network perimeter to block access to suspicious links targeting internal PACS systems

# Example Content Security Policy header configuration for Apache
# Add to .htaccess or Apache configuration file
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; frame-ancestors 'self';"

# Example for Nginx
# Add to nginx.conf server block
add_header Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; frame-ancestors 'self';" always;