CVE-2025-8910
📋 TL;DR
CVE-2025-8910 is a reflected cross-site scripting vulnerability in WellChoose's Organization Portal System that allows unauthenticated attackers to execute arbitrary JavaScript in victims' browsers through phishing links. This affects all users of the vulnerable portal system who click malicious links, potentially leading to session hijacking, credential theft, or malware installation.
💻 Affected Systems
- WellChoose Organization Portal System
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers steal administrator credentials, gain full system access, exfiltrate sensitive organizational data, and deploy ransomware across the network.
Likely Case
Attackers steal user session cookies to impersonate legitimate users, access confidential portal information, and perform unauthorized actions within user permissions.
If Mitigated
With proper web application firewalls and input validation, attackers can only execute limited JavaScript in isolated browser contexts with minimal impact.
🎯 Exploit Status
Exploitation requires user interaction (clicking malicious link) but requires no authentication. Attackers can craft phishing emails with malicious URLs containing JavaScript payloads.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 2.4.7
Vendor Advisory: https://www.twcert.org.tw/en/cp-139-10325-70192-2.html
Restart Required: No
Instructions:
1. Download version 2.4.7 from WellChoose's official distribution channel. 2. Backup current installation and configuration. 3. Replace vulnerable files with patched versions. 4. Verify all customizations remain functional.
🔧 Temporary Workarounds
Web Application Firewall (WAF) Rule
allDeploy WAF rules to block requests containing suspicious JavaScript patterns in URL parameters
# Example ModSecurity rule: SecRule ARGS "<script" "id:1001,phase:2,deny,status:403,msg:'XSS Attempt'"
# Example naxsi rule: MainRule "str:<script" "msg:XSS script tag" "mz:ARGS|BODY|URL|$HEADERS_VAR:Cookie" "s:$XSS:4" id:1001;
Content Security Policy (CSP)
allImplement strict CSP headers to prevent execution of inline JavaScript and restrict script sources
# Add to HTTP response headers: Content-Security-Policy: default-src 'self'; script-src 'self' https://trusted.cdn.com; object-src 'none';
🧯 If You Can't Patch
- Deploy a web application firewall with XSS protection rules to filter malicious requests before they reach the application
- Implement network segmentation to isolate the portal system from critical internal resources and monitor all outbound connections
🔍 How to Verify
Check if Vulnerable:
Test by accessing the portal with a URL containing a simple XSS payload like: https://portal.example.com/search?q=<script>alert('test')</script> and checking if JavaScript executesCheck Version:
Check the portal's admin interface or view page source for version information. Typically found in footer comments or /about page.Verify Fix Applied:
After patching, repeat the vulnerability test and confirm JavaScript does not execute. Also verify the application properly encodes or rejects malicious input.📡 Detection & Monitoring
Log Indicators:
- HTTP requests containing <script>, javascript:, or other XSS patterns in URL parameters
- Multiple failed login attempts from same IP after XSS payload requests
- Unusual user-agent strings containing JavaScript code
Network Indicators:
- Outbound connections to suspicious domains following portal access
- Unusual traffic patterns from user workstations to the portal system
SIEM Query:
source="web_logs" AND (url="*<script>*" OR url="*javascript:*" OR url="*onload=*" OR url="*onerror=*")