CVE-2023-24676 is a vulnerability identified in ProcessWire version 3.0.210, a popular open-source content management system (CMS). The flaw resides in the module installation process, specifically through the download_zip_url parameter. An attacker with administrative privileges can exploit this vulnerability to execute arbitrary code on the server by installing a malicious module that includes a reverse shell payload. This allows the attacker to gain remote control over the affected system. The vulnerability is categorized under CWE-94 (Improper Control of Generation of Code), indicating that the system does not properly restrict code execution during module installation. However, the exploit requires that the attacker already have admin-level access to the ProcessWire installation, which is a significant barrier. This has led to some dispute about the severity of the vulnerability since ProcessWire admins are inherently permitted to install any module, including those with arbitrary code. The CVSS v3.1 score of 7.2 reflects a high severity, with network attack vector, low attack complexity, high privileges required, no user interaction, and high impact on confidentiality, integrity, and availability. No patches or fixes are currently linked, and no known exploits have been reported in the wild as of the publication date. The vulnerability highlights the risk of privilege misuse or compromised admin credentials in ProcessWire environments.

For European organizations using ProcessWire CMS, this vulnerability poses a significant risk if an attacker gains administrative access. Successful exploitation can lead to full system compromise, including data theft, service disruption, and lateral movement within the network. The ability to install a reverse shell enables persistent remote access, which can be leveraged for further attacks or espionage. Organizations with multiple administrators or weak internal controls around admin credential management are particularly vulnerable. Given the high impact on confidentiality, integrity, and availability, this vulnerability could disrupt business operations, damage reputation, and lead to regulatory non-compliance under GDPR if personal data is exposed. The lack of known exploits reduces immediate risk but does not eliminate it, especially in targeted attacks or insider threat scenarios.

1. Restrict administrative access to ProcessWire installations to trusted personnel only and enforce strong authentication mechanisms, such as multi-factor authentication (MFA). 2. Regularly audit and monitor admin activities, especially module installations and changes to system configurations. 3. Implement network segmentation to limit access to the CMS backend and reduce the attack surface. 4. Review and validate all installed modules to ensure they come from trusted sources and have not been tampered with. 5. Keep ProcessWire installations updated and monitor official channels for patches addressing this vulnerability. 6. Employ intrusion detection and prevention systems to detect unusual activities such as reverse shell connections. 7. Conduct regular security training for administrators to recognize phishing and credential compromise risks. 8. Consider implementing application whitelisting or code integrity verification to prevent unauthorized code execution.