CVE-2026-5179: Doctors Appointment System SQLi Flaw

CVE-2026-5179 Overview

A SQL injection vulnerability has been identified in SourceCodester Simple Doctors Appointment System version 1.0. This vulnerability exists in the /admin/login.php file, where the Username parameter is not properly sanitized before being used in SQL queries. Attackers can exploit this flaw remotely to manipulate database queries, potentially leading to unauthorized data access, data manipulation, or complete database compromise.

Critical Impact

This SQL injection vulnerability allows unauthenticated remote attackers to bypass authentication, extract sensitive patient and administrative data, and potentially gain full control over the application's database. The exploit has been publicly disclosed, increasing the risk of active exploitation.

Affected Products

• SourceCodester Simple Doctors Appointment System 1.0
• /admin/login.php authentication component

Discovery Timeline

• 2026-03-31 - CVE-2026-5179 published to NVD
• 2026-04-01 - Last updated in NVD database

Technical Details for CVE-2026-5179

Vulnerability Analysis

This vulnerability is classified as CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component, commonly known as Injection). The application fails to properly sanitize user-supplied input in the Username field of the administrative login form before incorporating it into SQL queries. This allows an attacker to inject arbitrary SQL commands that are executed by the database server with the same privileges as the application.

The vulnerability is particularly concerning because it affects the administrative login portal, which represents a high-value target for attackers seeking to gain privileged access to the healthcare appointment system. Successful exploitation could expose sensitive patient health information, appointment records, and administrative credentials.

Root Cause

The root cause of this vulnerability is insufficient input validation and the likely use of unsanitized user input directly in SQL query construction. The application appears to concatenate the Username parameter directly into SQL statements without using parameterized queries, prepared statements, or proper input escaping mechanisms. This is a fundamental secure coding violation that enables classic SQL injection attacks.

Attack Vector

The attack can be executed remotely over the network without any authentication or user interaction. An attacker simply needs to craft a malicious HTTP request to the /admin/login.php endpoint with a specially crafted Username parameter containing SQL injection payloads.

The attacker can inject SQL commands through the login form's username field. Common exploitation techniques include:

• Authentication Bypass: Using payloads like ' OR '1'='1 to bypass login validation
• Data Extraction: Employing UNION-based injection to retrieve data from other database tables
• Database Enumeration: Using boolean-based or time-based blind injection to map database structure
• Privilege Escalation: Extracting administrator credentials or creating new admin accounts

For detailed technical information about the vulnerability mechanism, refer to the GitHub Issue Tracker and VulDB Vulnerability Listing.

Detection Methods for CVE-2026-5179

Indicators of Compromise

• Unusual or malformed requests to /admin/login.php containing SQL metacharacters such as single quotes, double dashes, semicolons, or SQL keywords
• Failed login attempts with abnormally long username values or special characters
• Database error messages appearing in HTTP responses that reveal query structure
• Unexpected database queries or access patterns in database audit logs
• Evidence of data exfiltration or unauthorized database reads in application logs

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block SQL injection patterns in the Username parameter
• Configure intrusion detection systems (IDS) to alert on requests containing common SQL injection payloads
• Enable and monitor database query logging for suspicious or malformed queries originating from the web application
• Deploy application-level logging to capture and analyze authentication attempts with unusual input patterns

Monitoring Recommendations

• Monitor HTTP access logs for repeated requests to /admin/login.php with varying payloads, which may indicate active exploitation attempts
• Set up alerts for database errors or exceptions that could indicate SQL injection probing
• Review authentication logs for anomalous login patterns, especially successful logins following multiple failed attempts
• Implement real-time monitoring for any unauthorized database schema access or data extraction activities

How to Mitigate CVE-2026-5179

Immediate Actions Required

• Restrict network access to the /admin/login.php endpoint to trusted IP addresses only using firewall rules or .htaccess configuration
• Deploy a Web Application Firewall (WAF) with SQL injection protection rules in front of the application
• Consider temporarily disabling the administrative login portal until a patch is applied
• Review database logs for any signs of previous exploitation and assess potential data exposure
• Notify affected parties if there is evidence of data compromise

Patch Information

At the time of publication, no official vendor patch has been released for this vulnerability. SourceCodester has been notified of the issue. Organizations using this software should monitor the SourceCodester website for security updates and apply patches as soon as they become available.

For additional vulnerability intelligence, refer to the VulDB CTI Information.

Workarounds

• Implement parameterized queries or prepared statements in the /admin/login.php file to prevent SQL injection
• Add server-side input validation to reject username values containing SQL metacharacters or exceeding expected length limits
• Place the application behind a reverse proxy with SQL injection filtering capabilities
• Implement additional authentication factors (IP whitelisting, CAPTCHA, MFA) to reduce attack surface on the admin login
• Consider replacing or removing the vulnerable application component if patching is not feasible

# Example: Apache .htaccess IP restriction for admin directory
<Directory "/var/www/html/admin">
    Order Deny,Allow
    Deny from all
    Allow from 192.168.1.0/24
    Allow from 10.0.0.0/8
</Directory>