CVE-2026-5180: Doctors Appointment System SQLi Vulnerability

CVE-2026-5180 Overview

A SQL injection vulnerability has been identified in SourceCodester Simple Doctors Appointment System 1.0. This flaw affects the login functionality within the file /admin/ajax.php?action=login2, where improper handling of the email parameter allows attackers to inject malicious SQL queries. The vulnerability can be exploited remotely without authentication, potentially enabling unauthorized access to the application's backend database.

Critical Impact

Attackers can exploit this SQL injection vulnerability to bypass authentication, extract sensitive patient and appointment data, modify database records, or potentially gain administrative access to the healthcare appointment system.

Affected Products

• SourceCodester Simple Doctors Appointment System 1.0
• Applications using the vulnerable /admin/ajax.php?action=login2 endpoint
• Healthcare systems built on this SourceCodester template

Discovery Timeline

• 2026-03-31 - CVE-2026-5180 published to NVD
• 2026-04-01 - Last updated in NVD database

Technical Details for CVE-2026-5180

Vulnerability Analysis

This vulnerability is classified as an injection flaw (CWE-74) affecting the admin login functionality of the Simple Doctors Appointment System. The application fails to properly sanitize user-supplied input in the email parameter before incorporating it into SQL queries. When a user submits login credentials through the /admin/ajax.php?action=login2 endpoint, the backend PHP code directly concatenates or interpolates the email value into the SQL statement without adequate validation or parameterization.

The network-accessible nature of this vulnerability means that any remote attacker can craft malicious requests targeting the login endpoint. No prior authentication is required to attempt exploitation, making this vulnerability particularly dangerous for internet-facing deployments. Successful exploitation could lead to authentication bypass, data exfiltration, or database manipulation.

Root Cause

The root cause of this vulnerability lies in the improper handling of user input within the login authentication mechanism. The application code fails to implement parameterized queries or prepared statements when processing the email parameter. Instead of treating user input as data, the vulnerable code treats it as part of the SQL command structure, allowing attackers to alter the intended query logic.

This is a common pattern in PHP applications where string concatenation is used to build SQL queries directly from request parameters. The absence of input validation, escaping, or the use of secure database abstraction layers creates this exploitable condition.

Attack Vector

The attack can be executed remotely over the network by sending crafted HTTP POST requests to the /admin/ajax.php?action=login2 endpoint. An attacker would manipulate the email parameter to include SQL metacharacters and injection payloads. Common exploitation techniques include:

The attacker sends a malicious value in the email field that terminates the legitimate query string and appends additional SQL commands. This could involve boolean-based blind injection to extract data character by character, UNION-based injection to retrieve data from other tables, or time-based blind injection using database sleep functions. The exploit has been publicly disclosed, meaning technical details and proof-of-concept methods are available to potential attackers. For technical details, refer to the GitHub CVE Issue and VulDB #354248.

Detection Methods for CVE-2026-5180

Indicators of Compromise

• Unusual or malformed HTTP requests to /admin/ajax.php?action=login2 containing SQL syntax characters such as single quotes, double dashes, semicolons, or UNION keywords in the email parameter
• Database query errors or anomalies logged by the application indicating syntax errors from injected content
• Unexpected administrative logins or session creation without corresponding valid credential usage
• Database audit logs showing unusual SELECT, UNION, or data extraction queries targeting user or patient tables

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block SQL injection patterns in the email parameter of requests to /admin/ajax.php
• Configure intrusion detection systems to alert on HTTP traffic containing common SQL injection signatures targeting the vulnerable endpoint
• Enable database query logging and monitor for queries containing suspicious patterns originating from the web application
• Deploy SentinelOne Singularity Platform to detect post-exploitation behaviors such as unauthorized database access or data exfiltration attempts

Monitoring Recommendations

• Monitor web server access logs for repeated requests to /admin/ajax.php?action=login2 with varying payloads in the email field
• Set up alerts for authentication events where the email field contains non-standard characters or exceeds typical length
• Review database logs for failed queries that may indicate injection attempts or successful data extraction
• Implement real-time monitoring of administrative access patterns to identify anomalous login activity

How to Mitigate CVE-2026-5180

Immediate Actions Required

• Immediately restrict access to the /admin/ajax.php endpoint using network-level controls or .htaccess rules until a patch can be applied
• Implement a Web Application Firewall with SQL injection detection rules to filter malicious requests
• Review application logs for evidence of prior exploitation attempts and assess potential data breach
• If possible, take the vulnerable application offline or place it behind VPN-only access until remediation is complete
• Contact SourceCodester or check community resources for updated versions of the Simple Doctors Appointment System

Patch Information

As of the last NVD update on 2026-04-01, no official vendor patch has been documented. Organizations using SourceCodester Simple Doctors Appointment System should monitor the SourceCodester website for security updates. Given the open-source nature of SourceCodester projects, administrators may need to apply manual code fixes or implement compensating controls. Check the VulDB vulnerability submission and VulDB #354248 CTI for community-provided mitigation guidance.

Workarounds

• Modify the vulnerable PHP code to use prepared statements with parameterized queries instead of direct string concatenation for the email input
• Implement server-side input validation to reject email values containing SQL metacharacters or exceeding expected format patterns
• Add application-level rate limiting on the login endpoint to slow down automated injection attempts
• Deploy network segmentation to limit database access from the web application tier to only required operations

# Configuration example - Apache .htaccess to restrict admin access
<Files "ajax.php">
    Order Deny,Allow
    Deny from all
    Allow from 192.168.1.0/24
    Allow from 10.0.0.0/8
</Files>