CVE-2026-4066
Smart Custom Fields <= 5.0.6 - Missing Authorization to Authenticated (Contributor+) Sensitive Information Exposure via Relational Post Search
Description
The Smart Custom Fields plugin for WordPress is vulnerable to unauthorized access of data due to a missing capability check on the relational_posts_search() function in all versions up to, and including, 5.0.6. This makes it possible for authenticated attackers, with Contributor-level access and above, to read private and draft post content from other authors via the smart-cf-relational-posts-search AJAX action. The function queries posts with post_status=any and returns full WP_Post objects including post_content, but only checks the generic edit_posts capability instead of verifying whether the requesting user has permission to read each individual post.
INFO
Published Date :
March 23, 2026, 11:17 p.m.
Last Modified :
March 23, 2026, 11:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-4066
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 Smart Custom Fields plugin to the latest version.
- Apply vendor patches if available.
- Verify the fix by testing user permissions.
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-2026-4066.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-4066 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-2026-4066
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-2026-4066 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-4066 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]
Mar. 23, 2026
Action Type Old Value New Value Added Description The Smart Custom Fields plugin for WordPress is vulnerable to unauthorized access of data due to a missing capability check on the relational_posts_search() function in all versions up to, and including, 5.0.6. This makes it possible for authenticated attackers, with Contributor-level access and above, to read private and draft post content from other authors via the smart-cf-relational-posts-search AJAX action. The function queries posts with post_status=any and returns full WP_Post objects including post_content, but only checks the generic edit_posts capability instead of verifying whether the requesting user has permission to read each individual post. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N Added CWE CWE-862 Added Reference https://plugins.trac.wordpress.org/browser/smart-custom-fields/trunk/classes/fields/class.field-related-posts.php#L101 Added Reference https://plugins.trac.wordpress.org/browser/smart-custom-fields/trunk/classes/fields/class.field-related-posts.php#L143 Added Reference https://plugins.trac.wordpress.org/browser/smart-custom-fields/trunk/classes/fields/class.field-related-posts.php#L78 Added Reference https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&new=3485210%40smart-custom-fields%2Ftrunk&old=3416964%40smart-custom-fields%2Ftrunk&sfp_email=&sfph_mail=#file2 Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/87f52e3a-e414-4f47-b46c-e3811e76744b?source=cve