CVE-2006-4210 in phPay
Summary
by MITRE
nu_mail.inc.php in Andreas Kansok phPay 2.02 and 2.02.1, when register_globals is enabled, allows remote attackers to use the server as an open mail relay via modified mail_text2, user_row[5], nu_mail_1, and shop_mail parameters. NOTE: some of these details are obtained from third party information.
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Analysis
by VulDB Data Team • 07/14/2024
The vulnerability identified as CVE-2006-4210 affects phPay 2.02 and 2.02.1 content management systems where the register_globals PHP configuration setting is enabled. This flaw represents a critical security weakness that enables remote attackers to exploit the system as an open mail relay, potentially allowing unauthorized email transmission through the vulnerable server. The vulnerability specifically targets the nu_mail.inc.php include file which handles email functionality within the phPay framework.
The technical implementation of this vulnerability stems from improper input validation and parameter handling within the mail relay functionality. Attackers can manipulate four specific parameters including mail_text2, user_row[5], nu_mail_1, and shop_mail to bypass normal email sending restrictions. When register_globals is enabled, PHP automatically creates global variables from request data, creating a dangerous condition where user-supplied input directly influences the application's mail sending behavior without proper sanitization. This configuration effectively transforms the vulnerable server into an open relay that can be used to send spam or malicious emails through the compromised system.
The operational impact of this vulnerability extends beyond simple email relay abuse. Attackers can leverage this weakness to conduct spam campaigns, send phishing emails, or use the compromised server for other malicious activities while maintaining anonymity through the relay. The vulnerability creates a persistent threat vector that can be exploited repeatedly, potentially leading to the server being blacklisted by email providers and resulting in reputation damage for the affected organization. Additionally, this open relay capability can be combined with other attack vectors to create more sophisticated multi-stage attacks.
From a cybersecurity framework perspective, this vulnerability aligns with CWE-20, which describes improper input validation, and maps to ATT&CK technique T1192, specifically open relay abuse. The vulnerability demonstrates the critical importance of secure coding practices and proper PHP configuration management. Organizations should implement immediate mitigations including disabling register_globals in PHP configurations, implementing proper input validation and sanitization for all user-supplied parameters, and monitoring email relay functionality for unusual activity patterns. Additionally, network-level restrictions and email server configuration hardening should be implemented to prevent unauthorized relay usage. The vulnerability serves as a prime example of how legacy PHP configurations can create persistent security risks when not properly managed, emphasizing the need for regular security audits and proper security patch management across all web applications.