What the vulnerability does
01Description
The Mailgun Subscriptions plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'mailgun_subscription_form' shortcode in all versions up to, and including, 1.3.1 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
Explanation of Vulnerability in Simple Terms
02Summary
The Mailgun Subscriptions plugin contains a cross-site scripting (XSS) vulnerability in versions up to 1.3.1. An authenticated user with low privileges can inject malicious scripts that execute in other users' browsers, potentially stealing session data or performing actions on their behalf. The vulnerability affects the entire site scope due to how the plugin processes user input.
What an attacker can do
03Attacker Capabilities
Inject malicious scripts that run in other users' browsers and steal their session data or perform actions as them.
Potential impact on your site
04Site Impact
Any authenticated user can compromise other users' accounts or sessions through script injection in the plugin.
Conditions required to exploit
05Prerequisites
Attacker must have a low-privilege account on the site; no user interaction required from the victim.
Key dates
06Disclosure timeline
December 12, 2025
CVE published
April 8, 2026
Record updated
