6.1
MEDIUM CVSS 3.1
CVE-2026-4091
OPEN-BRAIN <= 0.5.0 - Cross-Site Request Forgery
Description

The OPEN-BRAIN plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 0.5.0. This is due to missing nonce verification on the settings form in the func_page_main() function. This makes it possible for unauthenticated attackers to inject malicious web scripts via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

INFO

Published Date :

April 15, 2026, 9:16 a.m.

Last Modified :

April 22, 2026, 8:23 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-4091 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
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM MITRE-CVE
CVSS 3.1 MEDIUM [email protected]
Solution
Update the OPEN-BRAIN plugin to version 0.5.1 or later to fix CSRF vulnerability.
  • Update the OPEN-BRAIN plugin to version 0.5.1 or later.
  • Verify nonce checks are implemented for all forms.
  • Implement CSRF protection measures.
  • Educate users about phishing risks.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-4091 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-2026-4091 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-2026-4091 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-4091 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]

    Apr. 15, 2026

    Action Type Old Value New Value
    Added Description The OPEN-BRAIN plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 0.5.0. This is due to missing nonce verification on the settings form in the func_page_main() function. This makes it possible for unauthenticated attackers to inject malicious web scripts via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
    Added CWE CWE-352
    Added Reference https://plugins.trac.wordpress.org/browser/open-brain/tags/0.5.0/index.php#L237
    Added Reference https://plugins.trac.wordpress.org/browser/open-brain/tags/0.5.0/index.php#L252
    Added Reference https://plugins.trac.wordpress.org/browser/open-brain/tags/0.5.0/index.php#L253
    Added Reference https://plugins.trac.wordpress.org/browser/open-brain/tags/0.5.0/index.php#L272
    Added Reference https://plugins.trac.wordpress.org/browser/open-brain/trunk/index.php#L237
    Added Reference https://plugins.trac.wordpress.org/browser/open-brain/trunk/index.php#L252
    Added Reference https://plugins.trac.wordpress.org/browser/open-brain/trunk/index.php#L253
    Added Reference https://plugins.trac.wordpress.org/browser/open-brain/trunk/index.php#L272
    Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/93df6480-9bb1-4f5d-bb39-ff1a01d739cf?source=cve
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.