CVE-2025-52816 is a high-severity vulnerability classified under CWE-98, which involves improper control of filenames used in include or require statements within PHP programs. Specifically, this vulnerability affects the themehunk Zita WordPress theme up to version 1.6.5. The flaw allows an attacker to perform a PHP Local File Inclusion (LFI) attack by manipulating the filename parameter used in include or require statements without proper validation or sanitization. This can lead to the inclusion and execution of arbitrary files on the server, potentially resulting in full compromise of the affected web server. The vulnerability has a CVSS 3.1 base score of 8.1, indicating a high level of severity. The vector string (AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H) shows that the attack can be performed remotely over the network without authentication or user interaction, but with high attack complexity. Successful exploitation impacts confidentiality, integrity, and availability, allowing attackers to read sensitive files, execute arbitrary code, and disrupt services. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability was published on June 27, 2025, and reserved on June 19, 2025. The affected product, Zita, is a popular WordPress theme developed by themehunk, widely used for building websites with PHP backend. The root cause is insufficient validation of user-controlled input used in PHP include/require statements, a common vector for LFI attacks. This vulnerability can be leveraged to escalate attacks such as remote code execution, data exfiltration, or server takeover if combined with other weaknesses or misconfigurations.

For European organizations, this vulnerability poses a significant risk, especially for those using WordPress websites with the Zita theme. Exploitation could lead to unauthorized access to sensitive data, including personal data protected under GDPR, resulting in regulatory penalties and reputational damage. The ability to execute arbitrary code or disrupt availability can lead to website defacement, service outages, or pivoting into internal networks. E-commerce sites, government portals, and critical infrastructure web services using this theme are particularly at risk. The high severity and remote exploitability without authentication increase the urgency of addressing this vulnerability. Additionally, the lack of patches or mitigations at the time of disclosure means organizations must proactively implement compensating controls to reduce exposure. The impact extends beyond the compromised website to potential lateral movement within corporate networks, risking broader enterprise security.

Given the absence of official patches, European organizations should immediately audit their WordPress installations to identify the use of the Zita theme, especially versions up to 1.6.5. If detected, organizations should consider temporarily disabling or replacing the theme with a secure alternative until a patch is available. Implementing Web Application Firewalls (WAFs) with rules to detect and block suspicious include/require parameter manipulations can provide interim protection. Restricting PHP file inclusion paths via configuration (e.g., open_basedir directive) can limit the scope of file inclusion attacks. Regularly monitoring web server logs for anomalous requests targeting include parameters is critical for early detection. Organizations should also ensure that file permissions on the server are strictly enforced to prevent unauthorized file access. Finally, maintaining an incident response plan tailored to web application compromises will help mitigate damage if exploitation occurs.