CVE-2015-9507 in Attach Accounts to Orders Extension
Summary
by MITRE
The Easy Digital Downloads (EDD) Attach Accounts to Orders extension for WordPress, as used with EDD 1.8.x before 1.8.7, 1.9.x before 1.9.10, 2.0.x before 2.0.5, 2.1.x before 2.1.11, 2.2.x before 2.2.9, and 2.3.x before 2.3.7, has XSS because add_query_arg is misused.
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Analysis
by VulDB Data Team • 02/08/2025
The vulnerability identified as CVE-2015-9507 affects the Easy Digital Downloads WordPress plugin ecosystem, specifically targeting the Attach Accounts to Orders extension. This security flaw exists within multiple versions of the Easy Digital Downloads platform, spanning from version 1.8.x through 2.3.x, where the plugin fails to properly sanitize user input before incorporating it into URL query parameters. The vulnerability stems from the improper usage of WordPress's add_query_arg function, which is designed to safely construct URLs by handling query parameters. When attackers exploit this weakness, they can inject malicious JavaScript code into URLs that are then executed in the context of other users' browsers, creating a cross-site scripting attack vector. The affected versions represent a significant portion of the plugin's user base, making this vulnerability particularly concerning for WordPress administrators managing e-commerce sites that rely on Easy Digital Downloads for their operations.
The technical implementation of this vulnerability occurs when the plugin processes user-supplied data through the add_query_arg function without adequate sanitization or validation. This function, when misused, fails to properly escape special characters that could allow attackers to inject malicious payloads into URL parameters. The flaw specifically impacts how the plugin handles account attachment functionality within order processing, where user-provided identifiers or account information are appended to URLs without proper input filtering. According to CWE-79, this vulnerability maps directly to Cross-Site Scripting, as it allows attackers to inject malicious scripts that execute in the victim's browser context. The ATT&CK framework categorizes this under T1059.007 for Scripting, as the attack vector relies on executing malicious code through web-based interfaces. The vulnerability is particularly dangerous because it can be exploited through normal user interactions with the plugin's order management features, requiring no special privileges or advanced knowledge of the system's internals.
The operational impact of CVE-2015-9507 extends beyond simple script execution, as successful exploitation could enable attackers to perform various malicious activities within the compromised user sessions. Attackers could potentially steal session cookies, redirect users to phishing sites, deface the e-commerce platform, or even gain unauthorized access to customer account information. The vulnerability affects the integrity and confidentiality of data within the Easy Digital Downloads ecosystem, particularly impacting the sensitive transactional information processed through the plugin. For WordPress administrators, this represents a critical security gap that could lead to data breaches, loss of customer trust, and potential regulatory compliance violations. The widespread use of Easy Digital Downloads across numerous WordPress sites means that this vulnerability could affect hundreds or thousands of e-commerce operations, creating a substantial attack surface for threat actors. The risk is compounded by the fact that the vulnerability exists in multiple version streams, making it difficult for administrators to determine which specific patches are required for their installations.
The recommended mitigation strategy involves immediate upgrading to the patched versions of the Easy Digital Downloads plugin, specifically versions 1.8.7, 1.9.10, 2.0.5, 2.1.11, 2.2.9, and 2.3.7 respectively. Administrators should also implement additional security measures including regular plugin updates, monitoring for suspicious user activity, and implementing web application firewalls to detect and block malicious URL patterns. The fix addresses the core issue by properly sanitizing input parameters before they are passed to the add_query_arg function, ensuring that special characters are appropriately escaped. Security professionals should also consider implementing Content Security Policy headers to provide an additional layer of protection against XSS attacks. Organizations using older versions of the plugin should conduct thorough security assessments of their installations and monitor for any signs of exploitation attempts. The vulnerability highlights the importance of proper input validation and output escaping in web applications, particularly when dealing with user-supplied data that will be incorporated into dynamic URLs or HTML content. Regular security audits of WordPress plugins and themes remain essential for maintaining the overall security posture of e-commerce platforms and preventing similar vulnerabilities from being exploited in the future.