CVE-2025-54861: MedDream PACS Premium XSS Vulnerability

CVE-2025-54861 Overview

A reflected cross-site scripting (XSS) vulnerability exists in the modifyCoercion 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 user's privileges, potentially leading to session hijacking, credential theft, or unauthorized actions within the medical imaging system.

Critical Impact

Healthcare environments running MedDream PACS Premium are at risk of session hijacking and data exposure through malicious URLs that execute arbitrary JavaScript in authenticated user sessions.

Affected Products

• MedDream PACS Premium 7.3.6.870

Discovery Timeline

• 2026-01-20 - CVE CVE-2025-54861 published to NVD
• 2026-01-20 - Last updated in NVD database

Technical Details for CVE-2025-54861

Vulnerability Analysis

This reflected XSS vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation). The vulnerability resides in the modifyCoercion functionality of the MedDream PACS Premium web interface. When user-supplied input is processed by this function, the application fails to properly sanitize or encode the data before reflecting it back in the HTTP response.

MedDream PACS is a medical imaging software used in healthcare environments to view, process, and manage DICOM medical images. The presence of an XSS vulnerability in such a system is particularly concerning as it could potentially expose sensitive patient health information (PHI) and violate HIPAA compliance requirements.

The attack requires user interaction—specifically, a victim must click on a malicious URL. However, in healthcare environments where users routinely receive links via email or internal messaging systems, this social engineering aspect can be easily achieved.

Root Cause

The root cause of this vulnerability is insufficient input validation and output encoding in the modifyCoercion functionality. The application directly incorporates user-controlled data into the HTML response without proper sanitization, allowing malicious JavaScript payloads to be injected and executed in the browser context.

This type of flaw typically occurs when developers trust input parameters and fail to implement proper output encoding when rendering data back to users. The modifyCoercion endpoint appears to accept parameters that are reflected directly into the page without undergoing HTML entity encoding or other protective measures.

Attack Vector

The attack is conducted over the network and requires a victim to click on a crafted malicious URL. An attacker would construct a URL containing JavaScript code in one of the parameters processed by the modifyCoercion function. When the victim navigates to this URL while authenticated to the MedDream PACS system, the malicious script executes within their browser session.

Typical attack scenarios include:

• Session Hijacking: Stealing session cookies to impersonate the victim
• Credential Theft: Injecting fake login forms to capture credentials
• Data Exfiltration: Accessing and transmitting sensitive medical records
• Privilege Escalation: Performing administrative actions if the victim has elevated privileges

The vulnerability mechanism involves improper handling of URL parameters in the modifyCoercion endpoint. When a user visits a crafted URL, the malicious JavaScript payload embedded in the URL parameters is reflected back in the server response without proper encoding, causing the browser to execute the script. For detailed technical information, refer to the Talos Intelligence Vulnerability Report.

Detection Methods for CVE-2025-54861

Indicators of Compromise

• Unusual URL patterns containing JavaScript code or encoded script tags in requests to the modifyCoercion endpoint
• Web server logs showing requests with suspicious parameters such as <script>, javascript:, or encoded variants like %3Cscript%3E
• Unexpected outbound connections from client browsers to external domains following access to MedDream PACS
• Reports from users about unexpected behavior or prompts when clicking links related to the PACS system

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block common XSS payloads in HTTP requests
• Configure intrusion detection systems (IDS) to alert on patterns indicative of reflected XSS attempts
• Enable detailed access logging on the MedDream PACS web server and monitor for suspicious parameter values
• Deploy browser-based security solutions that can detect and prevent XSS execution attempts

Monitoring Recommendations

• Review web server access logs regularly for requests containing script tags or JavaScript protocol handlers
• Monitor network traffic for unusual data exfiltration patterns from systems accessing MedDream PACS
• Implement Content Security Policy (CSP) headers and monitor for CSP violation reports
• Configure SIEM rules to correlate authentication events with suspicious URL access patterns

How to Mitigate CVE-2025-54861

Immediate Actions Required

• Contact MedDream vendor for an updated version that addresses this vulnerability
• Implement Web Application Firewall rules to filter XSS payloads targeting the modifyCoercion endpoint
• Restrict access to the MedDream PACS system to trusted network segments only
• Educate users about the risks of clicking on unknown or suspicious URLs
• Consider implementing Content Security Policy headers to mitigate the impact of XSS attacks

Patch Information

Organizations should consult the Talos Intelligence Vulnerability Report for the latest patch information and vendor guidance. Contact MedDream support to obtain security updates that address CVE-2025-54861.

Workarounds

• Deploy a reverse proxy or WAF in front of MedDream PACS configured to sanitize or block requests containing XSS patterns
• Implement strict Content Security Policy (CSP) headers to prevent inline script execution
• Restrict access to the vulnerable modifyCoercion functionality if not required for normal operations
• Enable HTTP-only and Secure flags on session cookies to reduce the impact of potential session hijacking

# Example WAF rule for ModSecurity to block XSS attempts
SecRule ARGS "@detectXSS" "id:1001,phase:2,deny,status:403,msg:'XSS Attack Detected on modifyCoercion'"

# Example Content Security Policy header configuration for Apache
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'"