Auth bypass in Tomdever Wpforo Forum
CVE-2026-4666
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.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.
EPSS exploit prediction
EPSS: 0.003 (26.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 26th percentile — 26.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.003 · change: -0.001
Affected products
- Tomdever Wpforo Forum — versions 0
Weakness classification (CWE)
References
- www.wordfence.com/threat-intel/vulnerabilities/id/049ffab1-677d-4112-9f1d-092ee…
- plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/classes/Posts.php
- plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/classes/Posts.php
- plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/classes/Actions.php
- plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/includes/functions.php
- wordpress.org/plugins/wpforo/
- ti.wordfence.io/vendors/patch/1885/download
- plugins.trac.wordpress.org/changeset
Frequently asked questions
- What is CVE-2026-4666?
- CVE-2026-4666 is a medium-severity vulnerability in Tomdever Wpforo Forum, classified under Missing Authorization. CVSS score: 6.5/10. Published 2026-04-17.
- How severe is CVE-2026-4666?
- Medium severity. CVSS v3 base score is 6.5 out of 10.