CVE-2019-3848
A vulnerability was found in moodle before versions 3.6.3, 3.5.5 and 3.4.8. Permissions were not correctly checked before loading event information into the calendar’s edit event modal popup, so logged in non-guest users could view unauthorised calendar events. (Note: It was read-only access, users could not edit the events.)
Source: CVE-2019-3848