Mahara 15.04 before 15.04.15, 16.04 before 16.04.9, 16.10 before 16.10.6, and 17.04 before 17.04.4 are vulnerable to a user submitting a potential dangerous payload, e.g., XSS code, to be saved as their first name, last name, or display name in the profile fields that can cause issues such as escalation of privileges or unknown execution of malicious code when replying to messages in Mahara.