The WP Visitor Statistics (Real Time Traffic) plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'wsm_showDayStatsGraph' shortcode in all versions up to, and including, 8.4 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
https://plugins.trac.wordpress.org/browser/wp-stats-manager/trunk/includes/wsm_statistics.php#L2392
https://plugins.trac.wordpress.org/browser/wp-stats-manager/trunk/includes/wsm_statistics.php#L2272
https://plugins.trac.wordpress.org/browser/wp-stats-manager/trunk/includes/wsm_init.php#L208
https://plugins.trac.wordpress.org/browser/wp-stats-manager/tags/8.4/includes/wsm_init.php#L208