CVE-2026-111603 [MEDIUM] – PlayEdu through 2.3 contains a missing authorization vulnerability in the CourseController

PlayEdu through 2.3 contains a missing authorization vulnerability in the CourseController that allows authenticated students to access department-restricted courses by omitting the department visibility check. Attackers can enumerate sequential course and attachment IDs via the course details and attachment download endpoints to obtain course structure and attachment files from other departments.