CVE-2021-24839 : Exploit Details and Defense Strategies

This article provides an overview of CVE-2021-24839, a vulnerability found in the SupportCandy WordPress plugin before version 2.2.5 that could allow unauthenticated users to delete arbitrary tickets.

Understanding CVE-2021-24839

CVE-2021-24839 is a security flaw in the SupportCandy plugin that lacks proper authorization and Cross-Site Request Forgery (CSRF) checks, enabling unauthorized users to delete tickets without authentication.

What is CVE-2021-24839?

The SupportCandy WordPress plugin prior to version 2.2.5 is vulnerable to unauthenticated users invoking the wpsc_tickets AJAX action to delete arbitrary tickets. The lack of authorization and CSRF checks facilitates this unauthorized action.

The Impact of CVE-2021-24839

This vulnerability allows malicious actors to delete tickets on affected systems without authentication, potentially leading to data loss, service disruption, and unauthorized access to sensitive information.

Technical Details of CVE-2021-24839

The technical aspects of CVE-2021-24839 include a description of the vulnerability, affected systems, versions, and the exploitation mechanism.

Vulnerability Description

The absence of authorization and CSRF validation in the 'wpsc_tickets' AJAX action of the SupportCandy plugin allows unauthenticated users to delete tickets, posing a significant security risk.

Affected Systems and Versions

SupportCandy versions prior to 2.2.5 are impacted by this vulnerability. Specifically, version 2.2.5 and below lack necessary safeguards against unauthorized ticket deletion.

Exploitation Mechanism

By exploiting the lack of authentication checks in the 'wpsc_tickets' AJAX action, attackers can send malicious requests to delete tickets through the set_delete_permanently_bulk_ticket setting_action.

Mitigation and Prevention

Mitigating CVE-2021-24839 involves immediate steps to secure systems and implementing long-term security practices, along with timely patching and updates.

Immediate Steps to Take

Website administrators should update the SupportCandy plugin to version 2.2.5 or later to mitigate the vulnerability. Additionally, restricting access to sensitive functionalities can help prevent unauthorized ticket deletions.

Long-Term Security Practices

Implementing proper authorization and CSRF protection in WordPress plugins and regularly monitoring for security updates are crucial for maintaining a secure environment.

Patching and Updates

Developers should stay informed about security patches released by plugin developers and promptly apply these updates to address vulnerabilities and enhance the security posture of their WordPress websites.