CVE-2021-42663 in Online Event Booking and Reservation System
Summary
by MITRE • 11/05/2021
An HTML injection vulnerability exists in Sourcecodester Online Event Booking and Reservation System in PHP/MySQL via the msg parameter to /event-management/index.php. An attacker can leverage this vulnerability in order to change the visibility of the website. Once the target user clicks on a given link he will display the content of the HTML code of the attacker's choice.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 11/10/2021
The CVE-2021-42663 vulnerability represents a critical HTML injection flaw within the Sourcecodester Online Event Booking and Reservation System, a PHP/MySQL based web application designed for event management. This vulnerability specifically manifests through the msg parameter in the /event-management/index.php endpoint, creating a dangerous attack vector that allows malicious actors to manipulate the application's output behavior. The flaw resides in the application's insufficient input validation and output encoding mechanisms, failing to properly sanitize user-supplied data before incorporating it into the web page's HTML structure. The vulnerability's classification aligns with CWE-79 which describes Cross-Site Scripting (XSS) conditions where untrusted data is improperly embedded into HTML content, making it a direct descendant of the broader category of injection vulnerabilities.
The technical exploitation of this vulnerability enables attackers to inject arbitrary HTML and JavaScript code into the application's response, potentially allowing them to modify the website's visibility settings or display malicious content to unsuspecting users. When a victim clicks on a crafted link containing the malicious HTML payload, the attacker's code executes within the victim's browser context, creating a persistent threat that can compromise user sessions, steal sensitive information, or redirect users to malicious websites. The vulnerability's impact extends beyond simple content manipulation as it provides attackers with the ability to alter the application's behavior and potentially escalate privileges within the system's context. This type of vulnerability typically falls under the ATT&CK technique T1059.006 for Command and Scripting Interpreter, specifically through HTML/JavaScript injection methods.
The operational impact of CVE-2021-42663 is significant for organizations relying on the affected event booking system, as it creates a persistent threat vector that can be exploited to compromise user trust and system integrity. Attackers can leverage this vulnerability to perform session hijacking, deface the website, or redirect users to phishing sites that can harvest login credentials and personal information. The vulnerability's persistence means that once exploited, the malicious content can continue to affect users until the application is properly patched and the injected content is removed. Organizations using this system face potential regulatory compliance issues, as the vulnerability could lead to unauthorized data access and system compromise. The attack surface is particularly concerning given that the vulnerability requires minimal technical expertise to exploit, making it attractive to both skilled and less experienced attackers. Security professionals should note that this vulnerability represents a critical weakness in the application's input sanitization controls and requires immediate remediation through proper output encoding and input validation mechanisms to prevent successful exploitation attempts.