An issue was discovered in Telexy QPath 5.4.462. A low privileged authenticated user supplying a specially crafted serialized request to AdanitDataService.svc may modify user information, including but not limited to email address, username, and password, of other user accounts. The simplest attack approach is for the attacker to intercept their own password-change request and modify the username before the request reaches the server. Also, changing a victim's email address can have a similar account-takeover consequence.