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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
Low
Partial data modification
Availability
None
No disruption
CVSS Vector v3.1
Weakness Type (CWE)
References 6
https://plugins.trac.wordpress.org/browser/newsletters-lite/tags/4.17/includes/…
security@wordfence.com
https://plugins.trac.wordpress.org/browser/newsletters-lite/tags/4.17/wp-mailin…
security@wordfence.com
https://plugins.trac.wordpress.org/browser/newsletters-lite/tags/4.17/wp-mailin…
security@wordfence.com
https://plugins.trac.wordpress.org/browser/newsletters-lite/tags/4.17/wp-mailin…
security@wordfence.com
https://plugins.trac.wordpress.org/changeset?reponame=&old=3663788%40newsletter…
security@wordfence.com
https://www.wordfence.com/threat-intel/vulnerabilities/id/1d3eddce-1b41-4a33-8d…
security@wordfence.com