Critical severity · published Oct 14, 2026
CVE-2026-104748
SimpleForm <= 3.10.0 - Unauthenticated Privilege Escalation to wp_capabilities Mass Assignment via simpleform_wp_register
9.8
CVSS
0.8%
EPSS
No
On KEV
Description
The SimpleForm – Form Maker to Chat Apps with Quiz, Poll and Multi Lead Notifications plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 3.10.0 This is due to the `wp_ajax_nopriv_simpleform_wp_register` AJAX action lacking any capability check for role assignment and the `save_custom_fields_to_user_meta()` function using an exclusion list that omits `wp_capabilities`, combined with `get_form_settings()` returning a hard-coded defaults array that unconditionally enables meta writing regardless of the supplied `form_id`. This makes it possible for unauthenticated attackers to create a new Administrator-level WordPress account by supplying `wp_capabilities[administrator]=1` alongside standard registration fields. The nonce required by the endpoint is publicly emitted into the `front_end_data` JavaScript object on every front-end page via `wp_enqueue_scripts`, making it trivially obtainable by any unauthenticated visitor before submitting the malicious request.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 58% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SF
SimpleForm – Form Maker to Chat Apps with Quiz, Poll and Multi Lead Notifications · wpazleen
through 3.10.0 · source: vendor
Affected product
SF
SimpleForm – Form Maker to Chat Apps with Quiz, Poll and Multi Lead Notifications
wpazleen
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-104748
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-104748
www.wordfence.com
https://www.wordfence.com/threat-intel/vulnerabilities/id/b2b973fe-1209-43dc-b2a3-74086b12fe97?source=cve
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/simple-form/tags/3.10.0/app/Integrations/WordPressAuth.php#L291
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/simple-form/tags/3.10.0/app/Integrations/WordPressAuth.php#L184
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/simple-form/tags/3.10.0/app/Integrations/WordPressAuth.php#L32
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/simple-form/tags/3.10.0/app/Assets.php#L265
plugins.svn.wordpress.org
https://plugins.svn.wordpress.org/simple-form/trunk/
