CVE-2021-36621 in Online Covid Vaccination Scheduler System
Summary
by MITRE • 07/30/2021
Sourcecodester Online Covid Vaccination Scheduler System 1.0 is vulnerable to SQL Injection. The username parameter is vulnerable to time-based SQL injection. Upon successful dumping the admin password hash, an attacker can decrypt and obtain the plain-text password. Hence, the attacker could authenticate as Administrator.
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Analysis
by VulDB Data Team • 08/06/2021
The CVE-2021-36621 vulnerability affects the Sourcecodester Online Covid Vaccination Scheduler System version 1.0, representing a critical security flaw that enables unauthorized administrative access through SQL injection techniques. This vulnerability specifically targets the username parameter within the application's authentication mechanism, creating a pathway for malicious actors to exploit the system's database interactions. The vulnerability manifests as a time-based SQL injection attack, where the attacker leverages database timing characteristics to extract information from the backend system through carefully crafted malicious inputs.
The technical implementation of this vulnerability stems from inadequate input validation and sanitization within the application's user authentication flow. When a user attempts to log in, the system fails to properly escape or parameterize the username parameter before incorporating it into SQL queries. This allows attackers to inject malicious SQL code that manipulates the database query execution timing, enabling them to infer database contents through timing-based techniques. The vulnerability operates by constructing SQL statements that cause the database to pause execution for a specified duration when certain conditions are met, thereby revealing information about the database structure and contents through the timing variations in response times.
The operational impact of this vulnerability is severe and multifaceted, as it provides attackers with complete administrative control over the vaccination scheduling system. Successful exploitation enables attackers to dump the administrator password hash from the database, which can then be decrypted to obtain the plain-text password. This administrative access allows malicious actors to modify vaccination schedules, manipulate patient records, and potentially access sensitive health information of individuals. The vulnerability essentially undermines the entire security model of the system, as it bypasses all authentication mechanisms and provides unrestricted access to critical administrative functions. The implications extend beyond simple unauthorized access, potentially compromising patient privacy and the integrity of vaccination records that are crucial for public health management.
Security professionals should consider this vulnerability in the context of CWE-89 which categorizes SQL injection flaws as a fundamental weakness in application security. The attack pattern aligns with ATT&CK technique T1190, which describes the use of SQL injection to gain unauthorized access to databases. Mitigation strategies should include implementing proper input validation and parameterized queries to prevent SQL injection attacks. The system requires immediate patching with proper input sanitization, use of prepared statements, and implementation of proper authentication mechanisms including multi-factor authentication. Additionally, database access should be restricted through proper privilege management, ensuring that the application uses the minimum necessary database permissions. Network segmentation and intrusion detection systems should also be deployed to monitor for suspicious database access patterns and potential exploitation attempts.
This vulnerability highlights the critical importance of secure coding practices in healthcare applications, where the stakes are particularly high due to the sensitive nature of patient data. The ease with which an attacker can escalate privileges through SQL injection demonstrates the need for comprehensive security testing including automated vulnerability scanning and manual penetration testing. Organizations should implement regular security assessments and maintain up-to-date security patches to prevent similar vulnerabilities from being exploited in production environments. The incident also underscores the necessity of proper security training for developers working on applications that handle sensitive personal health information, ensuring they understand the principles of secure input handling and database interaction patterns that prevent injection attacks.