CVE-2025-67526 is a Remote File Inclusion vulnerability found in the ThimPress Sailing WordPress theme, affecting versions prior to 4.4.6. The vulnerability stems from improper validation and control of filenames used in PHP include or require statements. This flaw allows an attacker to manipulate the input parameter that determines which file is included, enabling them to specify a remote file hosted on an attacker-controlled server. When the vulnerable PHP code includes this remote file, it executes arbitrary PHP code within the context of the web server. This can lead to full remote code execution, allowing attackers to take over the affected website, steal sensitive data, modify content, or pivot to other internal systems. The vulnerability is categorized as a Remote File Inclusion (RFI), which is particularly dangerous because it does not require local access or authentication. Although no exploits are currently known in the wild, the public disclosure increases the risk of exploitation. The affected product, ThimPress Sailing, is a WordPress theme popular among European small and medium enterprises and bloggers, making the attack surface significant. The lack of a CVSS score means severity must be assessed based on impact and exploitability factors.

For European organizations, the impact of CVE-2025-67526 can be severe. Compromised websites can lead to data breaches involving customer information, intellectual property, or internal credentials. Attackers gaining remote code execution can deface websites, disrupt services, or use the compromised server as a foothold for further attacks within the corporate network. This can damage brand reputation and lead to regulatory penalties under GDPR if personal data is exposed. The vulnerability affects WordPress sites using the ThimPress Sailing theme, which is widely used in countries with strong WordPress market penetration such as Germany, the UK, France, Italy, and Spain. Organizations in sectors like e-commerce, media, and professional services are particularly at risk due to their reliance on WordPress for public-facing websites. The ease of exploitation without authentication increases the likelihood of automated scanning and attacks, potentially leading to widespread compromise if not addressed promptly.

1. Immediately update the ThimPress Sailing theme to version 4.4.6 or later, where the vulnerability is patched. 2. If updating is not immediately possible, disable or restrict access to vulnerable include/require functionality via web application firewall (WAF) rules that block suspicious input parameters or remote URL inclusion attempts. 3. Implement strict input validation and sanitization on all user-supplied parameters that influence file inclusion paths. 4. Disable allow_url_include and allow_url_fopen directives in PHP configurations to prevent remote file inclusion. 5. Conduct a thorough security audit of all WordPress themes and plugins to identify similar vulnerabilities. 6. Monitor web server logs for unusual requests attempting to exploit file inclusion. 7. Employ runtime application self-protection (RASP) or endpoint detection and response (EDR) tools to detect and block exploitation attempts. 8. Educate site administrators on the importance of timely updates and secure coding practices.