In WordPress before 4.7.3 (wp-includes/pluggable.php), control characters can trick redirect URL validation.
www.debian.org/security/2017/dsa-3815
www.securityfocus.com/bid/96600
www.securitytracker.com/id/1037959
codex.wordpress.org/Version_4.7.3
github.com/WordPress/WordPress/commit/288cd469396cfe7055972b457eb589cea51ce40e
wordpress.org/news/2017/03/wordpress-4-7-3-security-and-maintenance-release/
wpvulndb.com/vulnerabilities/8766