An issue was discovered in Mahara before 15.04.14, 16.x before 16.04.8, 16.10.x before 16.10.5, and 17.x before 17.04.3. When one closes the browser without logging out of Mahara, the value in the usr_session table is not removed. If someone were to open a browser, visit the Mahara site, and adjust the 'mahara' cookie to the old value, they can get access to the user's account.

Mahara 15.04 before 15.04.14 and 16.04 before 16.04.8 and 16.10 before 16.10.5 and 17.04 before 17.04.3 are vulnerable to a user submitting potential dangerous payload, e.g. XSS code, to be saved as their name in the usr_registration table. The values are then emailed to the the user and administrator and if accepted become part of the new user's account.