CVE-2015-7666 in Payment Form for PayPal Pro Plugin
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in the (1) cp_updateMessageItem and (2) cp_deleteMessageItem functions in cp_ppp_admin_int_message_list.inc.php in the Payment Form for PayPal Pro plugin before 1.0.2 for WordPress allow remote attackers to inject arbitrary web script or HTML via the cal parameter.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 01/28/2021
The vulnerability identified as CVE-2015-7666 represents a critical cross-site scripting weakness in the Payment Form for PayPal Pro WordPress plugin, affecting versions prior to 1.0.2. This issue resides within the administrative interface components of the plugin, specifically in the cp_updateMessageItem and cp_deleteMessageItem functions located in the cp_ppp_admin_int_message_list.inc.php file. The flaw manifests when the plugin processes the cal parameter without adequate input validation or output sanitization, creating an exploitable vector for malicious actors to inject arbitrary web scripts or HTML content into the administrative interface.
The technical nature of this vulnerability aligns with CWE-79, which specifically addresses cross-site scripting flaws where untrusted data is incorporated into web pages without proper validation or encoding. This weakness enables attackers to execute malicious scripts in the context of the affected administrator's browser session, potentially leading to complete compromise of the WordPress administrative interface. The cal parameter serves as the attack vector, allowing remote threat actors to inject malicious payloads that persist in the plugin's administrative message handling functionality.
The operational impact of this vulnerability extends beyond simple script injection, as it provides attackers with potential access to sensitive administrative functions within the WordPress environment. Successful exploitation could enable attackers to modify or delete critical payment form configurations, manipulate transaction records, or even escalate privileges within the compromised WordPress installation. The vulnerability affects the administrative interface specifically, meaning that an attacker would need to first gain access to an administrative account or find a way to exploit the XSS in a context where they could obtain administrative privileges.
From a threat modeling perspective, this vulnerability follows ATT&CK technique T1059.007 for Command and Scripting Interpreter, specifically focusing on script injection within web applications. The attack surface is particularly concerning as it targets the plugin's administrative functionality, which typically requires elevated privileges and contains sensitive configuration data. The vulnerability's persistence in the message list handling functions suggests that injected scripts could execute repeatedly whenever affected administrative pages are accessed, creating a long-term threat vector.
Mitigation strategies for this vulnerability include immediate patching to version 1.0.2 or later of the Payment Form for PayPal Pro plugin, which would address the input validation shortcomings in the affected functions. Administrators should also implement additional security measures such as restricting administrative access through strong authentication mechanisms, implementing web application firewalls to filter malicious input, and conducting regular security audits of installed plugins. The vulnerability demonstrates the importance of input validation in administrative interfaces, particularly for parameters that are processed within sensitive contexts where user input could directly impact system functionality and security posture.