CVE-2021-24615 in Wechat Reward Plugin
Summary
by MITRE • 10/18/2021
The Wechat Reward WordPress plugin through 1.7 does not sanitise or escape its QR settings, nor has any CSRF check in place, allowing attackers to make a logged in admin change the settings and perform Cross-Site Scripting attacks.
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Analysis
by VulDB Data Team • 10/22/2021
The CVE-2021-24615 vulnerability affects the Wechat Reward WordPress plugin version 1.7 and earlier, presenting a critical security flaw that combines multiple exploitation vectors. This vulnerability stems from the plugin's failure to implement proper input sanitization and cross-site request forgery protection mechanisms. The flaw allows authenticated attackers with administrative privileges to manipulate the plugin's QR code settings, creating a pathway for persistent cross-site scripting attacks. The vulnerability specifically targets the plugin's handling of QR settings parameters, which are processed without adequate sanitization or escaping measures, making them susceptible to malicious input injection.
The technical exploitation of this vulnerability occurs through the manipulation of the plugin's administrative interface where QR settings are configured. Attackers can leverage their administrative access to inject malicious JavaScript code into the QR configuration fields, which then executes whenever the settings page is accessed by other administrators or users with sufficient privileges. This creates a persistent XSS vector that can be used to hijack user sessions, steal sensitive information, or perform further malicious activities within the compromised WordPress environment. The absence of CSRF protection mechanisms means that attackers can craft malicious requests that trick administrators into executing unintended actions without their knowledge or consent.
The operational impact of CVE-2021-24615 extends beyond simple XSS execution, as it provides attackers with a foothold for more sophisticated attacks within the WordPress ecosystem. Once the initial XSS payload executes, attackers can potentially escalate privileges, modify plugin functionality, or redirect users to malicious sites. The vulnerability is particularly dangerous because it operates within the administrative context, allowing attackers to modify core plugin settings that may be used for legitimate business purposes. This creates a persistent threat that can remain undetected for extended periods while maintaining access to the compromised system.
Organizations affected by this vulnerability should immediately implement multiple mitigation strategies to address the security gap. The primary recommendation involves upgrading to the latest version of the Wechat Reward plugin where the sanitization and CSRF protection issues have been resolved. Additionally, administrators should review and harden their WordPress security configurations, including implementing proper input validation and output escaping mechanisms. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws, and with ATT&CK technique T1059.007 for script injection attacks. Security monitoring should include detection of unusual administrative activities and suspicious parameter modifications within plugin settings. Regular security audits and penetration testing should be conducted to identify similar vulnerabilities in other WordPress plugins that may lack proper sanitization and CSRF protection mechanisms.