Vulnerabilities and security researches forautomatic-thumbnail automatic-thumbnail

May 28, 2026

CVE, Research URL: CVE-2026-8899
Home page URL: Security reports for Auto Thumbnails
Application: Auto Thumbnails
Date: May 27, 2026
Research Description: The Auto Thumbnail plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'thumbnails' shortcode in all versions up to, and including, 1.0. This is due to insufficient input sanitization and output escaping on the shortcode's 'width' and 'height' attributes in the athn_thumbnails() function, which are concatenated directly into an HTML <img> tag. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
Affected versions: max 1.0.
Status: vulnerable