CVE-2025-53449 is a vulnerability classified as 'Improper Control of Filename for Include/Require Statement in PHP Program,' commonly known as a Remote File Inclusion (RFI) flaw, found in the axiomthemes Convex PHP theme up to version 1.11. This vulnerability arises when the application fails to properly validate or sanitize user-supplied input used in PHP include or require statements, allowing an attacker to specify arbitrary files to be included and executed by the server. The consequence is that an attacker can remotely execute arbitrary PHP code, leading to full compromise of the web server environment. The CVSS v3.1 score of 8.1 reflects a high severity, with attack vector being network (AV:N), requiring high attack complexity (AC:H), no privileges (PR:N), and no user interaction (UI:N). The scope is unchanged (S:U), but the impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H). Although no known exploits are currently reported in the wild, the vulnerability is publicly disclosed and thus may attract attackers. The vulnerability affects all installations of the Convex theme up to version 1.11, which is used in PHP-based web environments, often WordPress sites. The lack of patch links suggests that a fix may not yet be available, increasing urgency for mitigation.

For European organizations, this vulnerability poses a serious risk to web applications using the Convex theme. Successful exploitation can lead to remote code execution, allowing attackers to steal sensitive data, modify website content, deploy malware, or disrupt services. This can result in data breaches, reputational damage, regulatory penalties under GDPR, and operational downtime. Organizations in sectors such as finance, healthcare, government, and e-commerce are particularly vulnerable due to the sensitive nature of their data and services. The high attack complexity somewhat reduces the risk but does not eliminate it, especially for skilled attackers. The lack of required privileges or user interaction means the attack can be automated and launched remotely, increasing the threat surface. Given the widespread use of PHP and WordPress in Europe, the potential impact is broad, especially for small and medium enterprises that may lack robust security controls.

Immediate mitigation steps include: 1) Monitoring official axiomthemes channels for patches and applying them promptly once available. 2) In the absence of patches, implement strict input validation and sanitization on all parameters that influence file inclusion, using whitelisting approaches to restrict allowed file paths. 3) Configure PHP settings to disable remote file inclusion by setting 'allow_url_include' to 'Off' and 'allow_url_fopen' to 'Off' where feasible. 4) Employ web application firewalls (WAFs) with rules to detect and block suspicious file inclusion attempts. 5) Restrict file permissions and isolate web application directories to limit the impact of any successful exploitation. 6) Conduct regular security audits and penetration testing focused on file inclusion vulnerabilities. 7) Educate developers and administrators about secure coding practices related to file inclusion. 8) Maintain comprehensive logging and monitoring to detect anomalous behavior indicative of exploitation attempts.