{"id":"CVE-2026-4666","state":"PUBLISHED","title":"wpForo Forum <= 2.4.16 - Missing Authorization to Authenticated (Subscriber+) Arbitrary Forum Post Modification via 'guestposting' Parameter","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.","publishedAt":"2026-04-17T02:25:04.892Z","updatedAt":"2026-04-20T14:59:31.196Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","source":"Wordfence"},"assigner":"Wordfence","products":["tomdever wpForo Forum"],"affected":[{"vendor":"tomdever","product":"wpForo Forum","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"2.4.16","versionType":"semver"}]}],"references":["https://www.wordfence.com/threat-intel/vulnerabilities/id/049ffab1-677d-4112-9f1d-092ee01299f1?source=cve","https://plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/classes/Posts.php#L283","https://plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/classes/Posts.php#L285","https://plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/classes/Actions.php#L773","https://plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/includes/functions.php#L532","https://wordpress.org/plugins/wpforo/","https://ti.wordfence.io/vendors/patch/1885/download","https://plugins.trac.wordpress.org/changeset?old_path=%2Fwpforo/tags/2.4.16&new_path=%2Fwpforo/tags/2.4.17"],"weaknesses":["CWE-862"],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/4xxx/CVE-2026-4666.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-4666","state":"PUBLISHED","datePublished":"2026-04-17T02:25:04.892Z","dateUpdated":"2026-04-20T14:59:31.196Z","assignerShortName":"Wordfence","assignerOrgId":"b15e7b5b-3da4-40ae-a43c-f7aa60e62599","dateReserved":"2026-03-23T17:36:42.531Z"},"containers":{"cna":{"title":"wpForo Forum <= 2.4.16 - Missing Authorization to Authenticated (Subscriber+) Arbitrary Forum Post Modification via 'guestposting' Parameter","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"tomdever","product":"wpForo Forum","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"2.4.16","versionType":"semver"}]}],"references":[{"url":"https://www.wordfence.com/threat-intel/vulnerabilities/id/049ffab1-677d-4112-9f1d-092ee01299f1?source=cve"},{"url":"https://plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/classes/Posts.php#L283"},{"url":"https://plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/classes/Posts.php#L285"},{"url":"https://plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/classes/Actions.php#L773"},{"url":"https://plugins.trac.wordpress.org/browser/wpforo/tags/2.4.16/includes/functions.php#L532"},{"url":"https://wordpress.org/plugins/wpforo/"},{"url":"https://ti.wordfence.io/vendors/patch/1885/download"},{"url":"https://plugins.trac.wordpress.org/changeset?old_path=%2Fwpforo/tags/2.4.16&new_path=%2Fwpforo/tags/2.4.17"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","baseScore":6.5,"baseSeverity":"MEDIUM"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-862","lang":"en","description":"CWE-862 Missing Authorization","type":"CWE"}]}],"providerMetadata":{"shortName":"Wordfence","orgId":"b15e7b5b-3da4-40ae-a43c-f7aa60e62599","dateUpdated":"2026-04-17T02:25:04.892Z"},"credits":[{"lang":"en","type":"finder","value":"Jared Reyes"}],"timeline":[{"time":"2026-03-23T17:52:06.000Z","lang":"en","value":"Vendor Notified"},{"time":"2026-04-16T14:05:14.000Z","lang":"en","value":"Disclosed"}]},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-17T14:31:11.800069Z","id":"CVE-2026-4666","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-04-20T14:59:31.196Z"}}]}}}