CVE-2015-9280 – CVE-2015-9280 is an XML External Entity (XXE) v... (How to Fix)

Q: What is the severity of CVE-2015-9280?

CVE-2015-9280 has a CVSS score of 10.0 (CRITICAL). CVE-2015-9280 is an XML External Entity (XXE) vulnerability in MailEnable email server software. It allows attackers to read arbitrary files on the server or conduct server-side request forgery (SSRF) attacks by sending specially crafted XML documents to the request.aspx endpoint. Organizations running vulnerable versions of MailEnable are affected.

📋 TL;DR

CVE-2015-9280 is an XML External Entity (XXE) vulnerability in MailEnable email server software. It allows attackers to read arbitrary files on the server or conduct server-side request forgery (SSRF) attacks by sending specially crafted XML documents to the request.aspx endpoint. Organizations running vulnerable versions of MailEnable are affected.

💻 Affected Systems

Products:

MailEnable Standard Edition
MailEnable Professional Edition
MailEnable Enterprise Edition

Versions: All versions before 8.60

Operating Systems: Windows

Default Config Vulnerable: ⚠️ Yes

Notes: The vulnerability exists in the request.aspx component which is typically accessible via webmail interfaces or administrative interfaces.

📦 What is this software?

Mailenable by Mailenable

View all CVEs affecting Mailenable →

⚠️ Risk & Real-World Impact

🔴

Worst Case

Complete system compromise: attackers can read sensitive files (including configuration files with credentials), execute arbitrary code via SSRF, or cause denial of service.

🟠

Likely Case

Information disclosure: attackers can read arbitrary files from the server filesystem, potentially obtaining configuration files, passwords, or other sensitive data.

🟢

If Mitigated

Limited impact: with proper network segmentation and input validation, exploitation might be contained to specific directories or prevented entirely.

🌐 Internet-Facing: HIGH

🏢 Internal Only: MEDIUM

🎯 Exploit Status

Public PoC: ⚠️ Yes

Weaponized: LIKELY

Unauthenticated Exploit: ⚠️ Yes

Complexity: LOW

Exploitation requires sending a specially crafted HTTP request with XML payload to the vulnerable endpoint. Public exploit code and technical details are available in security advisories.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: 8.60 and later

Vendor Advisory: https://web.archive.org/web/20150329173628/http://www.mailenable.com/Standard-ReleaseNotes.txt

Restart Required: Yes

Instructions:

1. Download MailEnable version 8.60 or later from the official website. 2. Backup current configuration and data. 3. Run the installer to upgrade. 4. Restart MailEnable services. 5. Verify the installation completed successfully.

🔧 Temporary Workarounds

Disable XML external entity processing

windows

Configure the application to disable XXE processing in XML parsers

Modify web.config or application settings to set XmlResolver to null in XML parsers

Input validation filtering

windows

Implement input validation to reject XML documents containing external entity declarations

Add request filtering rules in IIS or application code to block requests containing DOCTYPE or ENTITY declarations

🧯 If You Can't Patch

Implement network segmentation: restrict access to MailEnable web interfaces to trusted networks only
Deploy a web application firewall (WAF) with XXE protection rules to block malicious requests

🔍 How to Verify

Check if Vulnerable:

Check the MailEnable version in the administrative interface or by examining installed programs in Control Panel. Versions below 8.60 are vulnerable.

Check Version:

Check MailEnable version via: 1. Open MailEnable Management console 2. Navigate to Help > About, or check installed programs in Windows Control Panel

Verify Fix Applied:

After upgrading, verify the version shows 8.60 or higher in the administrative interface. Test the request.aspx endpoint with a safe XXE test payload to confirm it's no longer vulnerable.

📡 Detection & Monitoring

Log Indicators:

HTTP requests to /request.aspx containing XML content with DOCTYPE or ENTITY declarations
Unusual file access patterns from the MailEnable process
Error logs showing XML parsing failures

Network Indicators:

HTTP POST requests to request.aspx with XML content-type
Outbound connections from MailEnable server to unexpected external systems (indicating SSRF)

SIEM Query:

source="mailenable.logs" AND (uri="/request.aspx" AND (content="DOCTYPE" OR content="ENTITY" OR content="SYSTEM"))

📊 Metadata

CVE ID: CVE-2015-9280

CVSS v3 Score: 10.0 (CRITICAL)

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

CWE: CWE-611

Published: January 16, 2019

Last Updated: November 21, 2024

🔗 References

https://web.archive.org/web/20150329173628/http://www.mailenable.com/Standard-ReleaseNotes.txt Release Notes,Third Party Advisory,Vendor Advisory
https://www.nccgroup.trust/globalassets/our-research/uk/technical-advisories/2015/technical-advisory-multiple-vulnerabilities-in-mailenable.pdf Exploit,Third Party Advisory
https://www.nccgroup.trust/uk/our-research/multiple-vulnerabilities-in-mailenable/ Third Party Advisory
https://web.archive.org/web/20150329173628/http://www.mailenable.com/Standard-ReleaseNotes.txt Release Notes,Third Party Advisory,Vendor Advisory
https://www.nccgroup.trust/globalassets/our-research/uk/technical-advisories/2015/technical-advisory-multiple-vulnerabilities-in-mailenable.pdf Exploit,Third Party Advisory
https://www.nccgroup.trust/uk/our-research/multiple-vulnerabilities-in-mailenable/ Third Party Advisory

📤 Share & Export

📄 Export Markdown 📋 Export JSON

🔗 Related Vulnerabilities

If you're affected by CVE-2015-9280, you might also want to check these: