CVE-2026-37600: Patient Appointment Scheduler SQLi Flaw

CVE-2026-37600 Overview

SourceCodester Patient Appointment Scheduler System v1.0 is vulnerable to SQL Injection in the file /scheduler/admin/appointments/view_details.php. This vulnerability allows an attacker with administrative privileges to inject malicious SQL queries through network-accessible endpoints, potentially leading to unauthorized data access from the backend database.

Critical Impact

Authenticated attackers with high privileges can exploit this SQL Injection vulnerability to extract sensitive patient appointment data and confidential information from the database.

Affected Products

• SourceCodester Patient Appointment Scheduler System v1.0
• Affected endpoint: /scheduler/admin/appointments/view_details.php

Discovery Timeline

• 2026-04-14 - CVE CVE-2026-37600 published to NVD
• 2026-04-14 - Last updated in NVD database

Technical Details for CVE-2026-37600

Vulnerability Analysis

This SQL Injection vulnerability (CWE-89) exists in the Patient Appointment Scheduler System's administrative interface. The vulnerable endpoint /scheduler/admin/appointments/view_details.php fails to properly sanitize user-supplied input before incorporating it into SQL queries. When an authenticated administrator accesses the view details functionality, malicious SQL statements can be injected to manipulate database queries.

The attack requires network access and high-level privileges (administrative authentication), which limits the potential attacker pool. However, once exploited, the vulnerability enables unauthorized read access to confidential database contents including patient records, appointment schedules, and potentially other sensitive healthcare-related information.

Root Cause

The root cause of this vulnerability is improper input validation and lack of parameterized queries in the view_details.php file. User-controlled input is directly concatenated into SQL query strings without proper escaping or use of prepared statements, allowing attackers to break out of the intended query context and execute arbitrary SQL commands.

Attack Vector

The attack vector is network-based, requiring the attacker to have authenticated administrative access to the Patient Appointment Scheduler System. The attacker can then craft malicious HTTP requests to the /scheduler/admin/appointments/view_details.php endpoint containing SQL injection payloads within parameters that are processed by the vulnerable code.

The vulnerability enables data exfiltration through techniques such as UNION-based injection or blind SQL injection to extract database contents one piece at a time. Given that this is a healthcare scheduling system, exposed data could include personally identifiable information (PII), medical appointment details, and other protected health information.

For detailed technical information about this vulnerability, refer to the GitHub SQL Vulnerability Report.

Detection Methods for CVE-2026-37600

Indicators of Compromise

• Unusual SQL error messages in application logs from the /scheduler/admin/appointments/view_details.php endpoint
• Suspicious administrative activity patterns including multiple rapid requests to the vulnerable endpoint
• Database query logs showing unexpected UNION SELECT, OR 1=1, or other SQL injection patterns
• Anomalous data access patterns in administrative session logs

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block common SQL injection patterns in requests to the scheduler application
• Monitor application logs for SQL syntax errors and database exceptions originating from administrative endpoints
• Deploy database activity monitoring to detect unusual query patterns or unauthorized data access
• Configure intrusion detection systems (IDS) with signatures for SQL injection attack patterns

Monitoring Recommendations

• Enable detailed logging for the Patient Appointment Scheduler administrative interface
• Implement real-time alerting for database errors and suspicious query patterns
• Monitor authentication logs for compromised administrative accounts that could be used to exploit this vulnerability
• Review administrative user activity regularly to detect potential exploitation attempts

How to Mitigate CVE-2026-37600

Immediate Actions Required

• Restrict network access to the administrative interface (/scheduler/admin/) to trusted IP addresses only
• Implement additional authentication controls such as multi-factor authentication for administrative users
• Review and audit administrative user accounts to ensure only authorized personnel have access
• Consider temporarily disabling the vulnerable view_details.php functionality until a patch is available

Patch Information

At the time of publication, no official vendor patch has been released for this vulnerability. Organizations using SourceCodester Patient Appointment Scheduler System v1.0 should monitor vendor communications for security updates and consider implementing the workarounds listed below.

For additional technical details, see the GitHub SQL Vulnerability Report.

Workarounds

• Implement input validation by modifying the view_details.php file to use prepared statements with parameterized queries
• Deploy a Web Application Firewall (WAF) with SQL injection protection rules in front of the application
• Restrict administrative interface access to internal networks only using firewall rules or VPN requirements
• Regularly audit database access logs for signs of SQL injection exploitation

# Configuration example: Restrict access to admin directory using Apache .htaccess
# Place this in /scheduler/admin/.htaccess

<RequireAll>
    Require ip 10.0.0.0/8
    Require ip 192.168.0.0/16
    Require ip 172.16.0.0/12
</RequireAll>

# For nginx, add to server block:
# location /scheduler/admin/ {
#     allow 10.0.0.0/8;
#     allow 192.168.0.0/16;
#     allow 172.16.0.0/12;
#     deny all;
# }