CVE-2026-96566
Description
The Newsletter – Send awesome emails from WordPress plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'np1' Custom Field Parameter in all versions up to, and including, 9.4.0 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. The subscription endpoint (na=sa) requires no nonce, no capability check, and no CAPTCHA, and the payload can be smuggled past email-address validation by embedding the {profile_1} placeholder in the local part of the submitted address, since WordPress's is_email() permits curly braces there.
Affected WordPress components
-
Newsletter – Send awesome emails from WordPress Plugin · newsletterUp to and including 9.4.0View on WordPress.org
-
newsletter Theme · newsletterUp to and including 9.4.0View on WordPress.org
A confirmed match is backed by the plugin or theme slug. A possible match is based on the product name only and should be verified.
Affected products and versions
- satollo Newsletter – Send awesome emails from WordPress — Up to and including 9.4.0
References
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/includes/classes.php#L212
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/includes/module-base.php#L1032
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/includes/module.php#L1006
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/plugin.php#L457
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/profile/profile.php#L511
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/subscription/subscription.php#L257
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/subscription/subscription.php#L723
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/changeset?reponame=&old=3711290%40newsletter&new=3711290%40newsletter
- www.wordfence.com https://www.wordfence.com/threat-intel/vulnerabilities/id/6e61119c-b83e-41b4-aa14-7dc61086520d?source=cve
- nvd.nist.gov Official NVD record