Authenticated Stored Cross-Site Scripting (XSS) in Simple Event Planner plugin <= 1.5.4 allows attackers with contributor or higher user roles to inject the malicious script by using vulnerable parameter &custom[add_seg][].

Multiple Authenticated Persistent Cross-Site Scripting (XSS) vulnerabilities in Simple Event Planner WordPress plugin <= 1.5.4 allows user with author or higher user rights inject the malicious code via vulnerable parameters: &custom[event_organiser], &custom[organiser_email], &custom[organiser_contact].