CVE-2025-58709 is a Remote File Inclusion (RFI) vulnerability found in the axiomthemes Legacy PHP product, affecting versions up to 1.9. The vulnerability arises from improper control over the filename parameter used in PHP include or require statements, allowing attackers to specify remote files that the server will include and execute. This leads to arbitrary code execution on the vulnerable server, compromising confidentiality, integrity, and availability. The vulnerability is remotely exploitable over the network without requiring authentication or user interaction, making it highly dangerous. The CVSS 3.1 score of 8.1 reflects the high impact and moderate attack complexity (AC:H), indicating some conditions must be met but no privileges or user interaction are needed. Although no public exploits are currently known, the nature of RFI vulnerabilities historically leads to rapid exploitation once disclosed. The vulnerability affects the Legacy product by axiomthemes, which is used in PHP-based web environments, often in content management systems or custom themes. Attackers can leverage this flaw to execute arbitrary PHP code, steal sensitive data, deface websites, or pivot within the network. The lack of patches at the time of disclosure increases the urgency for mitigation. The vulnerability was reserved in September 2025 and published in December 2025, indicating recent discovery. The technical root cause is insufficient sanitization or validation of input controlling the filename in include/require statements, a common PHP security pitfall. This vulnerability is critical for web-facing applications relying on Legacy themes, especially in environments where remote file inclusion is enabled or not properly restricted.

For European organizations, this vulnerability poses a significant risk to web servers running the axiomthemes Legacy product, potentially leading to full system compromise. Confidentiality is at risk as attackers can execute arbitrary code and access sensitive data stored on the server. Integrity is compromised because attackers can modify website content or inject malicious scripts. Availability may be affected if attackers disrupt services or deploy ransomware. Given the remote and unauthenticated nature of the exploit, attackers can target vulnerable systems at scale, increasing the likelihood of widespread attacks. Organizations in sectors with high web presence such as e-commerce, government, and media are particularly vulnerable. The impact extends to reputational damage, regulatory penalties under GDPR if personal data is exposed, and operational disruption. The lack of known exploits currently provides a window for proactive defense, but the high severity score demands urgent attention. European entities using PHP-based CMS or custom themes incorporating Legacy are at elevated risk, especially if remote file inclusion is not disabled in PHP configurations.

1. Immediately monitor vendor announcements and apply official patches or updates for axiomthemes Legacy as soon as they become available. 2. Implement strict input validation and sanitization on all parameters controlling file inclusion to prevent injection of remote URLs or arbitrary paths. 3. Disable allow_url_include and allow_url_fopen directives in PHP configuration to prevent remote file inclusion. 4. Employ web application firewalls (WAFs) with rules designed to detect and block suspicious include/require patterns and remote file inclusion attempts. 5. Conduct code audits to identify and refactor any insecure include/require statements that use user-controlled input. 6. Restrict file system permissions to limit the impact of any successful code execution. 7. Use network segmentation to isolate web servers from critical internal systems. 8. Monitor logs for unusual file inclusion or access patterns indicative of exploitation attempts. 9. Educate developers and administrators about secure coding practices related to file inclusion in PHP. 10. Consider deploying runtime application self-protection (RASP) solutions to detect and block exploitation in real time.