CVE-2015-9280 in MailEnable
Summary
by MITRE
MailEnable before 8.60 allows XXE via an XML document in the request.aspx Options parameter.
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Analysis
by VulDB Data Team • 05/02/2020
The vulnerability identified as CVE-2015-9280 affects MailEnable versions prior to 8.60 and represents a critical XML External Entity (XXE) flaw that can be exploited through the request.aspx Options parameter. This vulnerability falls under the CWE-611 weakness category, which specifically addresses Improper Restriction of XML External Entity Reference. The flaw enables attackers to inject malicious XML content that can cause the application to process external entities, potentially leading to unauthorized data access, server-side request forgery, or even remote code execution depending on the underlying system configuration.
The technical implementation of this vulnerability occurs within the MailEnable web interface where the request.aspx page processes user input through the Options parameter without proper sanitization or validation of XML content. When an attacker submits crafted XML data containing external entity references, the application's XML parser attempts to resolve these entities, creating an attack surface that can be leveraged for various malicious activities. The XXE vulnerability specifically exploits the way XML processors handle external entity declarations and references, allowing an attacker to access local files, perform port scans, or execute arbitrary commands on the server.
The operational impact of CVE-2015-9280 extends beyond simple data theft, as it can enable attackers to escalate privileges and gain unauthorized access to sensitive system resources. Attackers can utilize this vulnerability to read system files, access internal network services, or perform server-side request forgery attacks against other internal systems. The vulnerability is particularly dangerous because it operates at the application layer and can be exploited through standard web browser interactions, making it accessible to attackers with minimal technical expertise. This weakness aligns with ATT&CK technique T1059.007 for XML External Entity Processing and T1566 for Phishing with Malicious Attachments.
Mitigation strategies for this vulnerability require immediate patching of MailEnable to version 8.60 or later, which includes proper XML input validation and entity restriction mechanisms. Organizations should implement comprehensive web application firewalls that can detect and block XXE attack patterns, while also configuring proper XML parser settings to disable external entity resolution. Security measures should include input validation at multiple layers, including the application firewall, web server configuration, and application code level. Additionally, implementing network segmentation and privilege separation can limit the potential damage from successful exploitation. The remediation process must also include thorough security testing of all XML processing functions and regular vulnerability assessments to identify similar weaknesses in other applications that may be susceptible to the same class of attack.