CVE-2026-91092: wpForo Forum <= 3.1.5 - Missing Authorization to Authenticated (Subscriber+) Guest Post Takeover via wpforo_post_edit Action / Forged comment_author_email Cookie
The wpForo Forum plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 3.1.5. 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 subscriber-level access and above, to take over another guest author's forum post and modify its title, body, author name, and stored owner email address. This requires that guest posting and editing are enabled on the forum, and that the attacker knows the target guest author's email address.
Affected Software
Event History
Frequently Asked Questions
Which deployments are exposed to this issue?
Deployments running wpForo Forum 3.1.5 or earlier are exposed when both guest posting and guest-post editing are enabled on the forum. The affected posts are posts created by guest authors.
What does an attacker need to exploit it?
An attacker needs an authenticated WordPress account with at least Subscriber-level access and knowledge of the target guest author's email address. No user interaction is required.
What could an attacker change?
An attacker can take over another guest author's forum post and alter its title, body, author name, and stored owner email address.
What can be done while a patch is not available or cannot be applied?
Disable guest posting or guest-post editing on the forum to remove the required exploitation condition. Restricting untrusted authenticated users from obtaining Subscriber-or-higher accounts also reduces exposure.