Blocksy <= 2.0.39 - Authenticated (Contributor+) Stored Cross-Site Scripting via About Me block

The Blocksy theme for WordPress is vulnerable to Stored Cross-Site Scripting via the className parameter in the About Me block in all versions up to, and including, 2.0.39 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.