CVE-2025-34399
📋 TL;DR
MailEnable versions before 10.54 contain a reflected cross-site scripting vulnerability in the AddressesCc parameter of the address book page. Attackers can craft malicious URLs that execute JavaScript in victims' browsers when they attempt to send emails, potentially stealing session cookies or redirecting to malicious sites. This affects all MailEnable users running vulnerable versions who access the web interface.
💻 Affected Systems
- MailEnable
📦 What is this software?
Mailenable by Mailenable
⚠️ Risk & Real-World Impact
Worst Case
Attackers steal authenticated session cookies, hijack user accounts, redirect to phishing sites, and perform actions as authenticated users including email manipulation and data theft.
Likely Case
Attackers steal non-HttpOnly session cookies to hijack email accounts, redirect users to phishing pages, or inject malicious content into the email interface.
If Mitigated
With proper input validation and output encoding, the attack fails to execute, limiting impact to unsuccessful exploitation attempts.
🎯 Exploit Status
Exploitation requires victim interaction (clicking malicious link while authenticated); reflected XSS with known payload structure.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 10.54
Vendor Advisory: https://mailenable.com/Standard-ReleaseNotes.txt
Restart Required: Yes
Instructions:
1. Download MailEnable version 10.54 or later from official website. 2. Backup current configuration. 3. Run installer to upgrade. 4. Restart MailEnable services. 5. Verify version in admin interface.
🔧 Temporary Workarounds
Input Validation Filter
allImplement web application firewall or input validation to sanitize AddressesCc parameter
Disable Web Interface
windowsTemporarily disable webmail/administrative web interface if not required
Stop IIS service hosting MailEnable web interface
🧯 If You Can't Patch
- Implement strict Content Security Policy (CSP) headers to prevent script execution
- Deploy web application firewall with XSS protection rules for AddressesCc parameter
🔍 How to Verify
Check if Vulnerable:
Check MailEnable version in admin interface; if below 10.54, system is vulnerable.Check Version:
Check MailEnable Admin > System Information or review installation directory version filesVerify Fix Applied:
After patching, verify version shows 10.54 or higher in admin interface and test with safe XSS payload in AddressesCc parameter.📡 Detection & Monitoring
Log Indicators:
- Unusual GET requests to /Mondo/lang/sys/Forms/AddressBook.aspx with script tags in parameters
- Multiple failed login attempts followed by address book access
Network Indicators:
- HTTP requests containing JavaScript payloads in AddressesCc parameter
- Unusual redirects from MailEnable web interface
SIEM Query:
source="mailenable_logs" AND uri="/Mondo/lang/sys/Forms/AddressBook.aspx" AND (param="AddressesCc" AND value CONTAINS "script" OR "javascript:")