CVE-2021-24943 Scanner

The Registrations for the Events Calendar is a popular WordPress plugin used by event managers and organizers to streamline the registration process for various events directly from their WordPress websites. It allows for the creation of events with detailed descriptions, registration forms, and automatic confirmations, among other features, providing a comprehensive solution for managing event registrations. This plugin is widely used by businesses, organizations, and individuals managing both online and offline events. Its capabilities extend to handling multiple event categories, payment gateways, and it comes with custom notification settings. Among its numerous features, users can also customize the appearance and functionality to better align with their specific event needs. Its integration with WordPress enhances the content management system’s ability to support large scale and recurring events efficiently.

The SQL Injection vulnerability in the Registrations for the Events Calendar plugin before version 2.7.6 is particularly concerning due to its high severity and ease of exploitation. This vulnerability arises because the software does not properly sanitize and escape user-provided input for the 'event_id' parameter in the AJAX action 'rtec_send_unregister_link.' As a result, attackers can manipulate the SQL queries executed by the database, potentially reading sensitive data or executing malicious operations. Such vulnerabilities are typically exploited to access or manipulate databases indirectly through the frontend of the application. In this case, both unauthenticated and authenticated users could potentially exploit the system, increasing the risk and the potential attack surface. The release fixing this issue underscores the importance of validating and sanitizing all user inputs to prevent unauthorized database interactions.

From a technical perspective, the SQL Injection in this plugin is accessible via the 'rtec_send_unregister_link' AJAX action. By manipulating the 'event_id' parameter, attackers can inject SQL commands into the backend database queries. For example, the SQL command can be used to sleep the query execution for a specific period, as leveraged in time-based SQL injection attacks, to determine the validity of the input. The attack can be performed with a specially formatted HTTP POST request to 'wp-admin/admin-ajax.php' where the manipulated 'event_id' parameter is appended. If successfully executed, this query results in unauthorized data access and possible database damage or exfiltration. Time-based injections can additionally confirm the presence of vulnerable queries based on the response delay.

When this SQL Injection vulnerability is exploited, it can lead to various detrimental effects on the database and website functionality. Some of the severe impacts include unauthorized data access, where attackers can retrieve sensitive or confidential information stored within the database. Additionally, SQL Injection can allow attackers to delete or alter data, leading to data integrity issues and possible website defacement. Attackers might also insert malicious data into the database, which could then affect future transactions or website functionalities, leading to further compromise. In extreme cases, complete control over the database can be taken, posing a significant risk of further network infiltration and data breaches. This exploitation can disrupt the normal operation of events and registrations managed via the plugin, causing reputational and functional damages to the business.

REFERENCES

• https://wpscan.com/vulnerability/ba50c590-42ee-4523-8aa0-87ac644b77ed/
• https://nvd.nist.gov/vuln/detail/CVE-2021-24943
• https://wordpress.org/plugins/registrations-for-the-events-calendar/