The Zephyr Project Manager plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'zpm_profile_picture' parameter in all versions up to, and including, 3.3.209 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The injected payload is stored in the subscriber's own Zephyr profile and fires in any Administrator's browser session the first time the autocomplete mention lookup renders the avatar field, requiring no additional configuration beyond the plugin's default access_roles setting. Successful exploitation additionally requires an action by an administrator — the attacker cannot trigger the vulnerability on their own.