CVE-2024-10542 is a critical authorization bypass vulnerability identified in the WordPress plugin 'Spam protection, Anti-Spam, FireWall by CleanTalk' (all versions up to 6.43.2). The vulnerability stems from improper authorization checks in the checkWithoutToken function, which can be circumvented through reverse DNS spoofing. This flaw allows unauthenticated attackers to install and activate arbitrary plugins on the affected WordPress site. Since WordPress plugins run with high privileges, this arbitrary plugin installation can be leveraged to execute remote code, particularly if other vulnerable plugins are present. The vulnerability is classified under CWE-862 (Missing Authorization), highlighting the failure to enforce proper access controls. The CVSS v3.1 score of 9.8 reflects the ease of exploitation (network vector, no privileges or user interaction required) and the severe impact on confidentiality, integrity, and availability. Although no public exploits have been reported yet, the potential for exploitation is significant given the widespread use of WordPress and the CleanTalk plugin. The vulnerability affects all versions of the plugin, making immediate remediation critical. The lack of a patch link suggests that users must monitor vendor updates closely or consider temporary mitigations such as disabling the plugin or restricting access to the affected functionality.

The impact of CVE-2024-10542 is severe for organizations running WordPress sites with the CleanTalk plugin. Attackers can gain unauthorized administrative capabilities by installing and activating arbitrary plugins, which can lead to full site compromise, data theft, defacement, or use of the site as a pivot point for further attacks. Remote code execution enables attackers to execute arbitrary commands on the hosting server, potentially compromising the entire web server environment and connected infrastructure. This can result in loss of sensitive customer data, disruption of services, reputational damage, and regulatory penalties. Given WordPress's dominance in web hosting, this vulnerability poses a global risk to businesses, e-commerce platforms, blogs, and any organization relying on CleanTalk for spam protection. The ease of exploitation without authentication or user interaction increases the likelihood of automated attacks and widespread exploitation once public exploits emerge.

To mitigate CVE-2024-10542, organizations should immediately update the CleanTalk plugin to a version that addresses this vulnerability once released by the vendor. Until a patch is available, consider disabling the plugin to prevent exploitation. Restrict network access to the WordPress admin interface using IP whitelisting or VPNs to reduce exposure. Implement Web Application Firewalls (WAFs) with custom rules to detect and block suspicious requests involving DNS spoofing or unauthorized plugin installation attempts. Regularly audit installed plugins and remove any unnecessary or untrusted plugins to minimize attack surface. Monitor WordPress logs for unusual plugin installation or activation activities. Employ intrusion detection systems to identify exploitation attempts. Educate administrators on the risks of installing unverified plugins and enforce strict access controls on WordPress administrative accounts. Finally, maintain regular backups of website data and configurations to enable rapid recovery in case of compromise.