CVE-2026-4666
mediumpriority · track · 0OT risk · elevatedEPSS 0.003 · 26 %ileEUEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (1)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
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references (19)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2026-4666cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2026-4666cnnvd
- https://wordpress.org/plugins/wpforoPatchcnnvd
- https://plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/classes/Actions.php#L773enisa_euvd
- https://plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/classes/Posts.php#L283enisa_euvd
- https://plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/classes/Posts.php#L285enisa_euvd
- https://plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/includes/functions.php#L532enisa_euvd
- https://plugins.trac.wordpress.org/changeset?old_path=%2Fwpforo/tags/2.4.16&new_path=%2Fwpforo/tags/2.4.17enisa_euvd
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