During a security research I found an authenticated Stored XSS vulnerability. The name of the plugin is: WBW Currency Switcher for WooCommerce <= 1.6.6
The plugin does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup)
In the plugin's settings (WooCommerce > Settings > Currency > Frontend Switcher), tick "Enable switcher" and put the following payload in the "Panel header text" settings: <img src onerror=alert(/XSS/)> Save the settings. The XSS will be triggered when viewing the settings page again, as well as in any frontend page
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