CVE-2026-8868
Received Received - Intake
Stored XSS in Single Mailchimp WordPress Plugin

Publication date: 2026-05-27

Last updated on: 2026-05-27

Assigner: Wordfence

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.
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Meta Information
Published
2026-05-27
Last Modified
2026-05-27
Generated
2026-05-27
AI Q&A
2026-05-27
EPSS Evaluated
N/A
NVD
EUVD
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
mailchimp single_mailchimp to 1.4 (inc)
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
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CWE ID Description
CWE-79 The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?

The Single Mailchimp plugin for WordPress has a Stored Cross-Site Scripting (XSS) vulnerability in all versions up to and including 1.4. This occurs because the plugin does not properly sanitize or escape user-supplied shortcode attributes such as autocomplete, label, placeholder, btn_text, success_msg, and error_msg. These attributes are directly concatenated into the HTML output by the single_mailchimp() function, allowing an authenticated attacker with contributor-level access or higher to inject malicious scripts. These scripts execute whenever a user visits the affected page.


How can this vulnerability impact me? :

This vulnerability can allow an attacker with contributor-level access to inject arbitrary malicious scripts into pages on your WordPress site. When other users visit these pages, the injected scripts will execute in their browsers. This can lead to theft of user credentials, session hijacking, defacement of the website, or distribution of malware, compromising the security and integrity of your site and its users.


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