Wordfence

Wordfence is the most popular WordPress security solution, protecting over 3 million sites. It includes an endpoint firewall and malware scanner that were built from the ground up to protect WordPress. Our Threat Defense Feed arms Wordfence with the newest firewall rules, malware signatures and malicious IP addresses it needs to keep your website safe. Rounded out by a suite of additional features, Wordfence is the most comprehensive WordPress security option available. 

Learn more at https://www.wordfence.com