CVE-2012-5796 in PayPal Pro
Summary
by MITRE
The PayPal Pro module in osCommerce does not verify that the server hostname matches a domain name in the subject s Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate.
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Analysis
by VulDB Data Team • 02/11/2018
The vulnerability described in CVE-2012-5796 represents a critical SSL certificate validation flaw within the PayPal Pro module of osCommerce e-commerce platforms. This issue stems from improper SSL certificate verification mechanisms that fail to properly validate the hostname against the certificate's subject common name or subject alternative name fields. The absence of this crucial validation step creates a significant security gap that can be exploited by malicious actors to conduct man-in-the-middle attacks against unsuspecting users. The vulnerability specifically affects the SSL/TLS handshake process where the client should verify that the server certificate is valid for the domain it claims to represent.
The technical root cause of this vulnerability aligns with CWE-295, which addresses improper certificate validation in security protocols. When the osCommerce PayPal Pro module establishes SSL connections to PayPal's servers, it should perform hostname verification to ensure that the certificate presented by the server matches the expected domain. However, the module fails to implement this essential validation step, allowing attackers to present any valid SSL certificate during the handshake process. This flaw enables attackers to intercept sensitive transaction data, including customer payment information, user credentials, and other confidential data transmitted between the osCommerce store and PayPal's payment processing infrastructure.
The operational impact of this vulnerability extends beyond simple data interception, as it fundamentally undermines the trust model that SSL/TLS protocols are designed to provide. Attackers can exploit this weakness to create fake PayPal payment pages that appear legitimate to customers, potentially capturing sensitive payment information without detection. The vulnerability affects the entire payment processing workflow within osCommerce stores, making every transaction processed through the PayPal Pro module susceptible to interception. This weakness particularly impacts e-commerce environments where financial transactions are conducted, as the compromised system can be used to steal credit card information, personal identification details, and other sensitive data that customers expect to be protected during online payments.
Security professionals should implement immediate mitigations including updating the affected osCommerce installation to a patched version that properly implements SSL certificate hostname verification. The recommended approach involves configuring the system to perform strict certificate validation that checks both the subject common name and subject alternative name fields against the expected hostname. Organizations should also consider implementing additional network-level security controls such as certificate pinning to prevent the exploitation of this vulnerability. According to ATT&CK framework category T1573.002, this vulnerability represents an exploitation of secure communication protocols through improper certificate validation, which falls under the technique of "Tunneling through a proxy" and "Exfiltration over unencrypted or unauthenticated protocols." System administrators must also ensure that all SSL/TLS connections are properly configured to enforce certificate validation and that any custom payment module implementations follow industry best practices for secure communications. The vulnerability demonstrates the critical importance of proper SSL/TLS implementation in e-commerce environments and highlights the need for comprehensive security testing of third-party modules that handle sensitive financial data.