Vulnerability in satollo Newsletter – Send awesome emails from WordPress

[ Description ]Official 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.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ References ]References

• plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/includes/classes.php
• plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/includes/module-base.php
• plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/includes/module.php
• plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/plugin.php
• plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/profile/profile.php
• plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/subscription/subscription.php
• plugins.trac.wordpress.org/browser/newsletter/tags/9.3.9/subscription/subscription.php
• plugins.trac.wordpress.org/changeset
• www.wordfence.com/threat-intel/vulnerabilities/id/6e61119c-b83e-41b4-aa14-7dc61086520d