WPeMatico RSS Feed Fetcher <= 2.9 - Unauthenticated Stored Cross-Site Scripting via RSS Feed Content Import

The WPeMatico RSS Feed Fetcher plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 2.9 This is due to the plugin removing WordPress's wp_filter_post_kses filter from content_save_pre immediately before calling wp_insert_post() with RSS feed content, whenever the campaign's last editor had the unfiltered_html capability — a flag the plugin sets automatically for every admin-saved campaign. Imported item content is taken raw from $item->get_content(), only entity-decoded, and stored verbatim in post_content. This makes it possible for unauthenticated attackers, who publish or compromise an RSS feed that an administrator has subscribed a WPeMatico campaign to, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected imported post.