The SSL Zen — SSL Certificate Installer & HTTPS Redirects WordPress plugin before 4.7.40 does not perform capability or nonce checks on a certificate-file download routine that runs early in the WordPress admin request lifecycle, allowing any authenticated user, including Subscribers, to download the site's TLS private key, certificates, and diagnostic logs.
https://wpscan.com/vulnerability/858977f8-8ea3-4d3d-8967-31567f6786ff/