The Download Manager WordPress plugin before 7.5.6 does not sanitise and escape data submitted through its email-locked download subscription form before outputting it back in an admin page, which could allow unauthenticated attackers to perform Stored Cross-Site Scripting attacks against administrators. This affects the commercial Pro edition only; the free Download Manager WordPress plugin before 7.5.6 published under the same slug does not ship the affected feature.
https://wpscan.com/vulnerability/85ebf2d8-af69-434c-b733-8156210d6d6a/