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CVE-2026-4066 - Smart Custom Fields Plugin

CVE-2026-4066

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.

CVE-2026-4066

MEDIUM CVSS 4.3 Published 2026-03-23 Updated 2026-03-24
AI Risk Moderate (46/100) Active Exploit: No strong signal Published Exploit: No public exploit references Priority: P4 Planned
Severity Band MEDIUM
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Affected Components 1
Reference Links 5
AI Risk Engine Moderate (46/100)
Exploitability High
Active Exploitation No strong signal
Published Exploit Status No public exploit references

Threat Timeline

  1. 2026-03-23 CVE published and first recorded in the threat feed.
  2. 2026-03-24 Record updated with latest vulnerability metadata.
  3. 2026-04-09 AI technical context refreshed for mitigation and impact guidance.
  4. Now Monitoring for follow-up changes, linked references, and new related CVEs.

AI Context

Machine-generated threat intelligence

AI Updated 7 days ago

AI enriched 7 days ago (2026-04-09 06:18 UTC)

Technical Summary

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…

Potential Impact

Severity is MEDIUM (CVSS 4.3). Depending on deployment context, affected components may be exposed to unauthorized actions or data integrity risk.

Exploitability Assessment

Exploitability is assessed as High based on remote code execution potential.

Primary risk drivers: remote code execution potential

Mitigation Recommendations

Validate affected product versions, prioritize patching, and monitor references for vendor remediation guidance. If immediate patching is not possible, apply compensating controls and limit exposure of vulnerable surfaces.

Detection & Monitoring

Track authentication anomalies, unexpected file writes, and suspicious plugin API activity around affected components.

Business Impact Lens

Prioritize remediation where affected components process customer data, admin sessions, or Internet-exposed workflows.

Affected Products

Smart Custom Fields PLUGIN · smart-custom-fields Affected: <= 5.0.6 Fixed version not specified

References

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