CVE-2025-57881: MedDream PACS Server XSS Vulnerability

CVE-2025-57881 Overview

CVE-2025-57881 is a reflected cross-site scripting (XSS) vulnerability in the modifyEmail functionality of MedDream PACS Premium 7.3.6.870. An attacker who tricks an authenticated user into clicking a crafted URL can execute arbitrary JavaScript in the victim's browser session. The flaw is classified under [CWE-79] and affects medical imaging infrastructure used by healthcare providers.

Exploitation requires user interaction and low-privileged authentication, but the scope change in the CVSS vector indicates the impact can cross trust boundaries within the application context.

Critical Impact

Successful exploitation enables arbitrary JavaScript execution in the victim's authenticated session, allowing session theft, credential harvesting, or unauthorized actions against patient imaging data.

Affected Products

• MedDream PACS Premium 7.3.6.870
• MedDream PACS Server (Premium edition) — CPE cpe:2.3:a:meddream:pacs_server:7.3.6.870:*:*:*:premium:*:*:*
• Medical imaging deployments using the vulnerable modifyEmail endpoint

Discovery Timeline

• 2026-01-20 - CVE-2025-57881 published to NVD
• 2026-01-29 - Last updated in NVD database

Technical Details for CVE-2025-57881

Vulnerability Analysis

The vulnerability resides in the modifyEmail functionality of MedDream PACS Premium 7.3.6.870. The application reflects user-supplied input from a crafted URL back into the rendered HTML response without sufficient output encoding or input sanitization. An attacker constructs a malicious URL containing JavaScript payload parameters and delivers it to an authenticated PACS user through phishing or social engineering.

When the victim loads the URL, the application echoes the attacker-controlled content into the page, and the browser parses the injected script as legitimate code from the trusted PACS origin. The CVSS scope change reflects that script execution affects resources beyond the vulnerable component, including the user's authenticated session context and any data accessible through it.

Root Cause

The root cause is improper neutralization of input during web page generation [CWE-79]. The modifyEmail handler fails to apply contextual output encoding before reflecting parameter values into the HTTP response, allowing HTML and JavaScript metacharacters to be interpreted by the browser.

Attack Vector

The attack vector is network-based and requires user interaction. An attacker crafts a malicious URL targeting the modifyEmail endpoint with an embedded JavaScript payload. The attacker delivers the link to a PACS user, typically through email or messaging. Upon clicking the link, the victim's browser executes the injected JavaScript under the PACS application origin, granting access to session cookies, DOM contents, and authenticated API actions.

No verified public proof-of-concept code is available. Refer to the Talos Intelligence Vulnerability Report TALOS-2025-2263 for additional technical details from the reporting researchers.

Detection Methods for CVE-2025-57881

Indicators of Compromise

• HTTP requests to the modifyEmail endpoint containing URL-encoded <script> tags, javascript: URIs, or HTML event handlers such as onerror= and onload=
• Web server access logs showing unusually long query strings or encoded payloads targeting modifyEmail parameters
• Outbound browser requests from PACS users to attacker-controlled domains immediately after modifyEmail page loads

Detection Strategies

• Deploy web application firewall (WAF) rules that inspect query parameters to the modifyEmail endpoint for XSS signatures
• Correlate referer headers and access logs to identify externally originated links delivering crafted URLs to authenticated PACS sessions
• Monitor browser console error telemetry or Content Security Policy (CSP) violation reports from PACS clients for unexpected inline script execution

Monitoring Recommendations

• Enable verbose HTTP request logging on the MedDream PACS web tier and forward logs to a centralized SIEM for parameter inspection
• Alert on authenticated session anomalies such as concurrent sessions from new IP addresses or unusual API calls following modifyEmail access
• Track email security gateway events for messages containing URLs pointing to internal PACS hosts with suspicious query strings

How to Mitigate CVE-2025-57881

Immediate Actions Required

• Identify all MedDream PACS Premium 7.3.6.870 deployments and inventory exposed modifyEmail endpoints
• Contact MedDream support to obtain a patched build or vendor-supplied hotfix for the reflected XSS issue
• Restrict PACS web interface access to trusted networks or VPN-only routes until a fix is deployed
• Educate clinical and administrative users about the risk of clicking PACS-related links from untrusted sources

Patch Information

No vendor advisory or fixed version has been published in the available references at the time of NVD publication. Administrators should monitor the Talos Intelligence Vulnerability Report TALOS-2025-2263 and MedDream vendor channels for patch availability. Apply the fix to all affected instances once released.

Workarounds

• Deploy a reverse proxy or WAF with rules that strip or reject HTML and JavaScript metacharacters in modifyEmail request parameters
• Enforce a strict Content Security Policy on the PACS web application to block inline script execution and unauthorized script sources
• Require multi-factor authentication for PACS users to reduce the value of stolen session tokens obtained through XSS
• Set the HttpOnly and Secure flags on PACS session cookies to limit JavaScript access to authentication tokens

# Example NGINX reverse proxy rule blocking common XSS payloads to modifyEmail
location /modifyEmail {
    if ($args ~* "(<|%3C)\s*script|javascript:|onerror=|onload=") {
        return 403;
    }
    proxy_pass http://meddream-backend;
    add_header Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'";
    add_header X-XSS-Protection "1; mode=block";
}