BetterDocs < 4.5.4 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'blockId' Block Attribute

Description

The BetterDocs - Knowledge Base Docs & FAQ Solution for Elementor & Block Editor plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the blockId attribute of the betterdocs/category-slate-layout Gutenberg block in versions up to, and including, 4.5.3. This is due to insufficient input sanitization and output escaping in the CategorySlateLayout::render() method, which echoes the blockId block attribute directly into an HTML class attribute without esc_attr(). 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.