Custom Permalinks <= 2.6.0 - Authenticated(Editor+) Stored Cross-Site Scripting

The Custom Permalinks plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 2.6.0 due to insufficient input sanitization and output escaping on tag names. This allows authenticated users, with editor-level permissions or greater to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page, even when 'unfiltered_html' has been disabled.