Vulnerability in Gallery Custom Links — CVE-2026-107757
What to do now
Update Gallery Custom Links to 2.3.4 or later.
Affected versions
- Everything up to and including 2.3.3
Affected: Gallery Custom Links (plugin, gallery-custom-links)
What the vulnerability is
The Gallery Custom Links plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'display_name (profile.php) + comment (wp-comments-post.php)' parameter in all versions up to, and including, 2.3.3 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The exploit requires two coordinated inputs from the same authenticated attacker: an HTML comment payload stored in a comment body (preserved verbatim by WordPress comment kses) and a matching simple_html_dom noise key placed in the attacker's display_name (which survives esc_attr() intact), with substitution occurring after both filters have run during the plugin's default-on output-buffering pass over the full rendered page.
Sources
- https://plugins.trac.wordpress.org/browser/gallery-custom-links/tags/2.3.3/classes/core.php#L103
- https://plugins.trac.wordpress.org/browser/gallery-custom-links/tags/2.3.3/classes/core.php#L215
- https://plugins.trac.wordpress.org/browser/gallery-custom-links/tags/2.3.3/vendor/kub-at/php-simple-html-dom-parser/src/KubAT/PhpSimple/lib/simple_html_dom.php#L2112
- https://plugins.trac.wordpress.org/browser/gallery-custom-links/tags/2.3.3/vendor/kub-at/php-simple-html-dom-parser/src/KubAT/PhpSimple/lib/simple_html_dom.php#L2207
- https://plugins.trac.wordpress.org/browser/gallery-custom-links/tags/2.3.3/vendor/kub-at/php-simple-html-dom-parser/src/KubAT/PhpSimple/lib/simple_html_dom.php#L502
- https://plugins.trac.wordpress.org/changeset/3737485/gallery-custom-links