CVE-2026-3995
OPEN-BRAIN <= 0.5.0 - Authenticated (Administrator+) Stored Cross-Site Scripting via 'API Key' Setting
Description
The OPEN-BRAIN plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'API Key' settings field in all versions up to, and including, 0.5.0. This is due to insufficient input sanitization and output escaping. The plugin uses sanitize_text_field() which strips HTML tags but does not encode double quotes or other HTML-special characters needed for safe attribute context output. The API key value is saved via update_option() and later output into an HTML input element's value attribute without esc_attr() escaping. This makes it possible for authenticated attackers, with Administrator-level access, to inject arbitrary web scripts via attribute breakout payloads (e.g., double quotes followed by event handlers) that execute whenever a user accesses the plugin settings page.
INFO
Published Date :
April 16, 2026, 7:16 a.m.
Last Modified :
April 16, 2026, 7:16 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-3995
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 | MEDIUM | [email protected] |
Solution
- Update the OPEN-BRAIN plugin to the latest version.
- Ensure all user input is properly sanitized.
- Escape output for attribute contexts.
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-2026-3995.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-3995 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-2026-3995
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-2026-3995 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-3995 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.
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New CVE Received by [email protected]
Apr. 16, 2026
Action Type Old Value New Value Added Description The OPEN-BRAIN plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'API Key' settings field in all versions up to, and including, 0.5.0. This is due to insufficient input sanitization and output escaping. The plugin uses sanitize_text_field() which strips HTML tags but does not encode double quotes or other HTML-special characters needed for safe attribute context output. The API key value is saved via update_option() and later output into an HTML input element's value attribute without esc_attr() escaping. This makes it possible for authenticated attackers, with Administrator-level access, to inject arbitrary web scripts via attribute breakout payloads (e.g., double quotes followed by event handlers) that execute whenever a user accesses the plugin settings page. Added CVSS V3.1 AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N Added CWE CWE-79 Added Reference https://plugins.trac.wordpress.org/browser/open-brain/tags/0.5.0/index.php#L128 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#L128 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/3fe3fa95-cc1d-469b-8a97-37987b9ae362?source=cve