CVE-2026-12108

Description

The Highlighting Code Block plugin for WordPress is vulnerable to Stored Cross-Site Scripting via admin settings in all versions up to, and including, 2.2.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level permissions and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.

References

• https://plugins.trac.wordpress.org/browser/highlighting-code-block/tags/2.1.3/class/loos_hcb.php#L158
• https://plugins.trac.wordpress.org/browser/highlighting-code-block/tags/2.1.3/class/loos_hcb_menu.php#L23
• https://plugins.trac.wordpress.org/browser/highlighting-code-block/tags/2.1.3/class/loos_hcb_scripts.php#L69
• https://plugins.trac.wordpress.org/browser/highlighting-code-block/tags/2.2.0/class/loos_hcb.php#L158
• https://plugins.trac.wordpress.org/browser/highlighting-code-block/tags/2.2.0/class/loos_hcb_menu.php#L23