The MasterStudy LMS WordPress plugin from 1.9 before 3.7.50 does not verify that a course a member asks to enrol in is covered by their membership plan, nor that the plan identifier submitted with the request is one they actually hold, allowing any member to enrol themselves into restricted paid courses outside their plan and beyond the number of courses it entitles them to.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
High
Difficult to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
Low
Partial data leak
Integrity
Low
Partial data modification
Availability
None
No disruption
CVSS Vector v3.1