CVE-2026-6566: smub photo gallery, sliders, proofing and themes – nextgen gallery

Vulnerability summary

CVE-2026-6566 is a medium (CVSS 4.3) vulnerability in smub photo gallery, sliders, proofing and themes – nextgen gallery. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 17.3% of scored vulnerabilities. Fixed in 4.2.1.

Timeline

1. 20-05-2026
   PublishedVulnerability first disclosed.
2. 20-05-2026
   Last modifiedVulnerability information updated.

Description

The Photo Gallery, Sliders, Proofing and Themes – NextGEN Gallery plugin for WordPress is vulnerable to Insecure Direct Object Reference in versions up to and including 4.2.0. This is due to insufficient object-level authorization in the image deletion REST flow where the permission callback for DELETE /imagely/v1/images/{id} only checks 'NextGEN Manage gallery' permissions and does not enforce gallery ownership or 'NextGEN Manage others gallery' permissions. This makes it possible for authenticated attackers, with Subscriber-level privileges and 'NextGEN Manage gallery' capability, to delete gallery images belonging to other users as well as their associated image files from disk when deleteImg is enabled (default).

• CWE-639Authorization Bypass Through User-Controlled KeyThe system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.