WordPress through 4.8.2, when domain-based flashmediaelement.swf sandboxing is not used, allows remote attackers to conduct cross-domain Flash injection (XSF) attacks by leveraging code contained within the wp-includes/js/mediaelement/flashmediaelement.swf file.
Before version 4.8.2, WordPress mishandled % characters and additional placeholder values in $wpdb->prepare, and thus did not properly address the possibility of plugins and themes enabling SQL injection attacks.
In WordPress before 4.7.5, a cross-site scripting (XSS) vulnerability exists when attempting to upload very large files, because the error message does not properly restrict presentation of the filename.