Vulnerability 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.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://plugins.trac.wordpress.org/browser/smart-custom-fields/trunk/classes/fie
- https://plugins.trac.wordpress.org/browser/smart-custom-fields/trunk/classes/fie
- https://plugins.trac.wordpress.org/browser/smart-custom-fields/trunk/classes/fie
- https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&new
- https://www.wordfence.com/threat-intel/vulnerabilities/id/87f52e3a-e414-4f47-b46
FAQ
What is CVE-2026-4066?
CVE-2026-4066 is a vulnerability with a CVSS score of 4.3 (MEDIUM). 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 includi...
How severe is CVE-2026-4066?
CVE-2026-4066 has been rated MEDIUM with a CVSS base score of 4.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-4066?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.