Meks Flexible Shortcodes < 1.3.7 - Authenticated (Contributor+) Stored Cross-Site Scripting

Description

The Meks Flexible Shortcodes plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 1.3.6 due to insufficient input sanitization and output escaping. 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.