The MIR blocks and shortcodes plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'title' attribute (and other attributes such as 'ready_animation_text') of the 'msc_stats' shortcode in versions up to, and including, 1.0.0. This is due to insufficient input sanitization and output escaping on user supplied shortcode attributes inside the msc_stats() rendering function. 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.