CVE-2026-75908

Description

The Newsletters plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 4.17. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for authenticated attackers, with author-level access and above, to send arbitrary newsletter emails to users of any WordPress role, including administrators, by forging POST fields during a normal post submission. This allows an attacker-supplied role slug via the newsletters_mailinglistsroles POST field to be passed directly to get_users(), enabling unauthorized mass-mailing and potential phishing against privileged site users through the site's own outbound email channel.

References

• https://plugins.trac.wordpress.org/browser/newsletters-lite/tags/4.17/includes/checkinit.php#L63
• https://plugins.trac.wordpress.org/browser/newsletters-lite/tags/4.17/wp-mailinglist.php#L3897
• https://plugins.trac.wordpress.org/browser/newsletters-lite/tags/4.17/wp-mailinglist.php#L3957
• https://plugins.trac.wordpress.org/browser/newsletters-lite/tags/4.17/wp-mailinglist.php#L4114
• https://plugins.trac.wordpress.org/changeset?reponame=&old=3663788%40newsletters-lite&new=3663788%40newsletters-lite