Description
The Single Mailchimp plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'single-mailchimp' shortcode in all versions up to, and including, 1.4. This is due to insufficient input sanitization and output escaping on user-supplied shortcode attributes (autocomplete, label, placeholder, btn_text, success_msg, error_msg) which are concatenated directly into HTML output by the single_mailchimp() function in shortcodes.php. 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.
Problem types
CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Product status
Any version
Timeline
| 2026-05-26: | Disclosed |
Credits
Gilang Asra Bilhadi
References
www.wordfence.com/...-b6a3-43d9-a82d-5cbcffc39ad9?source=cve
plugins.trac.wordpress.org/...mailchimp/trunk/shortcodes.php
plugins.trac.wordpress.org/...mailchimp/trunk/shortcodes.php