CVE-2026-13439
Easy Form Builder by WhiteStudio <= 4.0.11 - Unauthenticated Privilege Escalation to Administrator via Password Recovery REST Endpoint
Description
The Easy Form Builder by WhiteStudio plugin for WordPress is vulnerable to Unauthenticated Privilege Escalation to Administrator in versions up to, and including, 4.0.11 This is due to the password recovery flow using the publicly-visible session identifier ('sid') as the password reset token stored in wp_emsfb_temp_links, combined with a publicly-accessible nonce refresh endpoint (Emsfb/v1/nonce/refresh) that issues valid WordPress REST nonces to unauthenticated visitors. This makes it possible for unauthenticated attackers to reset the password of any WordPress user — including administrators — by scraping the public sid from a published login form page, submitting a recovery request for any known user email via Emsfb/v1/forms/message/add, and then calling Emsfb/v1/forms/recovery/efb_set_password with the known sid to set an arbitrary new password and gain full administrator access.
INFO
Published Date :
July 21, 2026, 6:16 a.m.
Last Modified :
July 21, 2026, 6:16 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-13439
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | [email protected] | ||||
| CVSS 3.1 | CRITICAL | MITRE-CVE |
Solution
- Update the Easy Form Builder plugin to the latest version.
- Apply vendor patches for the authentication bypass.
- Verify session management and token handling.
- Review nonce generation and validation.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-13439.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-13439 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-13439
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-13439 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-13439 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Jul. 21, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'hassantafreshi', 'product': 'Easy Form Builder by WhiteStudio – Drag & Drop Form Builder', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '4.0.11'}], 'defaultStatus': 'unaffected'}] Added Description The Easy Form Builder by WhiteStudio plugin for WordPress is vulnerable to Unauthenticated Privilege Escalation to Administrator in versions up to, and including, 4.0.11 This is due to the password recovery flow using the publicly-visible session identifier ('sid') as the password reset token stored in wp_emsfb_temp_links, combined with a publicly-accessible nonce refresh endpoint (Emsfb/v1/nonce/refresh) that issues valid WordPress REST nonces to unauthenticated visitors. This makes it possible for unauthenticated attackers to reset the password of any WordPress user — including administrators — by scraping the public sid from a published login form page, submitting a recovery request for any known user email via Emsfb/v1/forms/message/add, and then calling Emsfb/v1/forms/recovery/efb_set_password with the known sid to set an arbitrary new password and gain full administrator access. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-269 Added Reference https://plugins.trac.wordpress.org/browser/easy-form-builder/trunk/includes/class-Emsfb-public.php#L1587 Added Reference https://plugins.trac.wordpress.org/browser/easy-form-builder/trunk/includes/class-Emsfb-public.php#L5024 Added Reference https://plugins.trac.wordpress.org/browser/easy-form-builder/trunk/includes/class-Emsfb-public.php#L5060 Added Reference https://plugins.trac.wordpress.org/browser/easy-form-builder/trunk/includes/class-Emsfb-public.php#L623 Added Reference https://plugins.trac.wordpress.org/browser/easy-form-builder/trunk/includes/class-Emsfb-public.php#L96 Added Reference https://plugins.trac.wordpress.org/changeset/3588226/easy-form-builder/trunk/includes/class-Emsfb-public.php Added Reference https://plugins.trac.wordpress.org/changeset?old_path=%2Feasy-form-builder/tags/4.0.11&new_path=%2Feasy-form-builder/tags/4.0.12 Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/df8326b6-a443-4f76-a755-49f89af74d7e?source=cve