kishan0725 Hospital Management System v4 contains an Insecure Direct Object Reference (IDOR) vulnerability in its appointment cancellation functionality. This flaw allows an attacker with limited privileges to access or manipulate appointment data they should not be authorized to access. The vulnerability has a CVSS 3.1 base score of 6.5, indicating a medium severity level. No public exploits or known active exploitation have been reported. No affected versions or patch information are provided.