e621ng before 26.09.16 Open Redirect via URL Parameters

e621ng versions before 26.09.16 pass untrusted request parameters directly to Rails url_for in PaginatorComponent and controller navigation links, allowing attackers to redirect pagination and navigation controls to attacker-controlled origins. Attackers can supply host, protocol, and port query parameters that are interpreted as URL generation options, causing pagination links to point to malicious domains while the initial page loads from the legitimate site.