CVE-2026-15790: Video Gallery <= 4.0.4 - Authenticated (Author+) Stored Cross-Site Scripting via Attachment 'post_title' via emd_mb_meta Shortcode

Vulnerability summary

CVE-2026-15790 is a medium (CVSS 6.4) Cross-site Scripting vulnerability in emarket-design video gallery – youtube gallery, playlist & video grid. EPSS estimates a 0.32% chance of exploitation in the next 30 days, higher than 23.8% of scored vulnerabilities. Fixed in 4.0.5.

Timeline

1. 16-08-2026
   PublishedVulnerability first disclosed.
2. 17-08-2026
   Last modifiedVulnerability information updated.

Description

The Youtube Showcase plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 4.0.4 via the 'emd_mb_meta' shortcode. This is due to insufficient input sanitization and output escaping on attachment titles referenced by the shortcode's image field: EMD_MB_Helper::image_info() returns the attachment's raw post_title, and EMD_MB_Helper::shortcode() interpolates it into title="%s" HTML attributes via sprintf() without esc_attr(). This makes it possible for authenticated attackers, with author-level access and above (upload_files capability required to create the attachment, edit_posts/publish_posts to embed the shortcode), to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.