GiveWP <= 4.17.0 - Authenticated (Contributor+) Stored Cross-Site Scripting via givewp_campaign_grid Shortcode Attributes

The GiveWP – Donation Plugin and Fundraising Platform plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's givewp_campaign_grid shortcode in versions up to, and including, 4.17.0 This is due to insufficient input sanitization and output escaping on user supplied shortcode attributes (filter_by, layout, sort_by, order_by) in the CampaignGridShortcode::parseAttributes() function combined with the render template emitting json_encode($attributes) inside a single-quoted HTML attribute without esc_attr() — json_encode() does not escape single quotes by default, so a ' in an attribute value breaks out of the enclosing attribute. 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.