The host is installed with Atlassian Jira Server before 7.13.16, 8.0.0 before 8.5.7 or 8.6.0 before 8.12.0 and is prone to an information disclosure vulnerability. A flaw is present in the application which fails to properly handle an issues in the /ViewUserHover.jspa endpoint. Successful exploitation could allow an unauthenticated user to enumerate users via /ViewUserHover.jspa endpoint.