The "Buy Me a Coffee – Button and Widget Plugin" plugin for WordPress is vulnerable to Cross-Site Scripting in versions up to, and including, 3.6 due to insufficient sanitization and escaping on the 'text value set via the bmc_post_reception action. This makes it possible for authenticated attackers, with subscriber-level permissions, and above to inject arbitrary web scripts into pages that execute whenever a victim accesses a page with the injected scripts.