Guest Author < 2.4 - Authenticated (Author+) Stored Cross-Site Scripting

Description The Guest Author plugin for WordPress is vulnerable to Stored Cross-Site Scripting via author name in versions up to, and including, 2.3 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with author-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.