CVE-2026-14335 in Easy Digital Downloads Plugin
Summary
by MITRE • 10/10/2026
The Easy Digital Downloads – eCommerce Payments and Subscriptions made easy plugin for WordPress is vulnerable to Stored Cross-Site Scripting via PayPal IPN Parameters in all versions up to, and including, 3.6.9 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
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Analysis
by VulDB Data Team • 10/10/2026
The vulnerability identified within the Easy Digital Downloads plugin for WordPress represents a significant security risk stemming from inadequate handling of external data inputs, specifically those originating from PayPal IPN parameters. This flaw is present in all versions up to and including 3.6.9 and is classified as a Stored Cross-Site Scripting issue. The core technical deficiency lies in the plugins failure to properly sanitize user-supplied input or escape output when processing these specific payment notification fields. Because the application accepts data from an external service without rigorous validation, it allows malicious actors to inject executable JavaScript code into the database through legitimate-looking transaction notifications. This lack of sanitization means that any special characters or script tags embedded within the IPN payload are preserved and rendered directly by the browser when the affected page is accessed.
From a technical perspective, this vulnerability exploits the trust relationship between the web application and its payment gateway integration. When PayPal sends an Instant Payment Notification to the WordPress site, the plugin processes various parameters associated with that transaction. Due to insufficient input sanitization, these parameters are stored in the database without filtering out potentially dangerous content. Subsequently, when a user or administrator views details related to this transaction on the frontend or backend of the website, the browser interprets the injected scripts as part of the page structure rather than plain text. This execution context allows the malicious code to run with the privileges and session cookies of the viewing user, effectively bypassing same-origin policies that are designed to prevent such attacks.
The operational impact of this Stored Cross-Site Scripting vulnerability is severe because it does not require the attacker to trick a specific target into clicking a crafted link in an email or social media post, which is typical for reflected XSS. Instead, the payload remains on the server until accessed by any user who views the compromised page. This persistence increases the likelihood of successful exploitation and broadens the scope of potential victims. An unauthenticated attacker can leverage this flaw to steal session cookies, hijack administrative sessions, deface websites, or redirect users to malicious sites designed for phishing or malware distribution. The ability to execute arbitrary web scripts means that attackers can manipulate the user interface, alter content dynamically, or perform actions on behalf of authenticated users without their knowledge or consent.
This vulnerability aligns with CWE-79, which describes Improper Neutralization of Input During Web Page Generation commonly known as Cross-site Scripting. Furthermore, in terms of tactical classification under the MITRE ATT&CK framework, this behavior corresponds to techniques involving client-side code injection and potentially credential access through browser session hijacking. The attack vector is categorized as unauthenticated because no prior login or valid credentials are required to inject the malicious payload via the PayPal IPN endpoint. This highlights a critical gap in the security architecture of the plugin where external data sources were not treated with appropriate skepticism regarding their content integrity.
To mitigate this vulnerability, users must upgrade the Easy Digital Downloads plugin to version 3.6.10 or later, which includes patches for input sanitization and output escaping mechanisms. Until an update is applied, administrators should consider temporarily disabling PayPal IPN notifications if feasible, although this may impact business operations. It is also advisable to implement a Web Application Firewall that can detect and block common XSS payloads in HTTP requests, providing an additional layer of defense against exploitation attempts. Regular security audits and code reviews focusing on data handling practices for third-party integrations are essential to prevent similar issues in the future. Ensuring that all external inputs are strictly validated against expected formats and that output is correctly encoded based on its context remains a fundamental best practice in secure software development.