Horde Groupware Webmail Edition through 5.2.22 allows XSS via an admin/user.php?form=update_f&user_name= or admin/user.php?form=remove_f&user_name= or admin/config/diff.php?app= URI.
https://www.exploit-db.com/exploits/46903
https://numanozdemir.com/respdisc/horde/horde.txt
https://numanozdemir.com/respdisc/horde/horde.mp4