CVE-2025-36556
📋 TL;DR
A reflected cross-site scripting vulnerability in MedDream PACS Premium's ldapUser functionality allows attackers to execute arbitrary JavaScript code by tricking users into clicking malicious URLs. This affects MedDream PACS Premium 7.3.6.870 installations with the vulnerable ldapUser component. Users who access crafted URLs could have their sessions hijacked or credentials stolen.
💻 Affected Systems
- MedDream PACS Premium
📦 What is this software?
Pacs Server by Meddream
⚠️ Risk & Real-World Impact
Worst Case
Attackers could steal administrator credentials, compromise patient data, pivot to internal systems, or deploy ransomware across the healthcare network.
Likely Case
Session hijacking, credential theft from users who click malicious links, and limited data exfiltration from vulnerable sessions.
If Mitigated
Minimal impact with proper input validation, output encoding, and Content Security Policy headers blocking script execution.
🎯 Exploit Status
Reflected XSS requires user interaction but is trivial to weaponize via phishing. No authentication needed to trigger the vulnerability.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://talosintelligence.com/vulnerability_reports/TALOS-2025-2272
Restart Required: No
Instructions:
1. Contact MedDream vendor for patch availability. 2. Apply vendor-provided security update. 3. Test functionality after patching. 4. Monitor for any regression issues.
🔧 Temporary Workarounds
Implement WAF Rules
allDeploy web application firewall rules to block XSS payloads in URL parameters
# Example ModSecurity rule: SecRule ARGS "<script" "id:1001,phase:2,deny,status:403,msg:'XSS Attack Detected'"
# Cloudflare WAF: Enable XSS protection rules
Content Security Policy
allImplement strict CSP headers to prevent inline script execution
# Apache: Header set Content-Security-Policy "default-src 'self'; script-src 'self'"
# Nginx: add_header Content-Security-Policy "default-src 'self'; script-src 'self';" always;
🧯 If You Can't Patch
- Disable ldapUser functionality if not required for operations
- Implement network segmentation to isolate MedDream PACS from internet access
🔍 How to Verify
Check if Vulnerable:
Test by accessing the ldapUser endpoint with XSS payloads in URL parameters and checking if scripts executeCheck Version:
Check MedDream PACS version in administration interface or configuration filesVerify Fix Applied:
Retest with XSS payloads after applying mitigations to confirm scripts no longer execute📡 Detection & Monitoring
Log Indicators:
- Unusual URL parameters containing script tags or JavaScript code
- Multiple failed login attempts from same IP
- Suspicious user-agent strings
Network Indicators:
- HTTP requests with encoded script payloads in query strings
- Outbound connections to suspicious domains after accessing MedDream URLs
SIEM Query:
source="meddream_logs" AND (url="*<script*" OR url="*javascript:*" OR url="*onerror=*" OR url="*onload=*")