wpForo Forum: A security weakness
wpForo Forum is affected by a security weakness. Exploitation requires at least subscriber-level access. The resulting impact depends on how the affected component exposes the vulnerable operation. The published affected range is <= 2.4.16.
- Component
- wpForo Forum
- Plugin slug
wpforo- Affected
- <= 2.4.16
- Safe version
> 2.4.16- Published
- Apr 17, 2026
- Weakness
- CWE-862 — Missing Authorization
This CVE was published Apr 17, 2026 and is one of 47 known issues for this plugin.
Update, patch or deactivate.
Update wpForo Forum to a release after 2.4.16, or disable and remove it until a fixed version is available.
A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.
Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.
Technical description
The wpForo Forum plugin for WordPress is vulnerable to unauthorized modification of data due to the use of `extract($args, EXTR_OVERWRITE)` on user-controlled input in the `edit()` method of `classes/Posts.php` in all versions up to, and including, 2.4.16. The `post_edit` action handler in `Actions.php` passes `$_REQUEST['post']` directly to `Posts::edit()`, which calls `extract($args, EXTR_OVERWRITE)`. An attacker can inject `post[guestposting]=1` to overwrite the local `$guestposting` variable, causing the entire permission check block to be skipped. The nonce check uses a hardcoded `wpforo_verify_form` action shared across all 8 forum templates, so any user who can view any forum page obtains a valid nonce. This makes it possible for authenticated attackers, with Subscriber-level access and above, to edit the title, body, name, and email fields of any forum post, including posts in private forums, admin posts, and moderator posts. Content passes through `wpforo_kses()` which strips JavaScript but allows rich HTML.
CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Primary and upstream sources
- NVD record for CVE-2026-4666
- WordPress upstream reference plugins.trac.wordpress.org
- WordPress upstream reference plugins.trac.wordpress.org
- WordPress upstream reference plugins.trac.wordpress.org
- WordPress upstream reference plugins.trac.wordpress.org
- WordPress upstream reference plugins.trac.wordpress.org
- Upstream reference ti.wordfence.io
- WordPress.org plugin page wordpress.org
- Wordfence advisory wordfence.com