CVE-2025-67526 is a critical vulnerability classified under CWE-98 (Improper Control of Filename for Include/Require Statement in PHP Program), affecting the ThimPress Sailing WordPress theme versions prior to 4.4.6. This vulnerability allows an attacker to perform Remote File Inclusion (RFI) by manipulating the filename parameter used in PHP include or require statements. Because the application does not properly validate or sanitize the input controlling the file path, an attacker can supply a remote URL pointing to malicious PHP code. When the vulnerable application includes this remote file, the attacker's code executes with the same privileges as the web server, potentially leading to full system compromise. The vulnerability requires no authentication or user interaction and can be exploited remotely over the network. The CVSS v3.1 base score of 9.8 reflects the critical nature of this flaw, with high impact on confidentiality, integrity, and availability. Although no public exploits have been reported yet, the vulnerability's characteristics make it a prime target for attackers seeking to gain unauthorized control over affected systems. The lack of an official patch at the time of publication increases the urgency for organizations to apply workarounds or mitigations. This vulnerability is particularly dangerous in shared hosting or multi-tenant environments where compromise of one site can lead to broader impacts.

For European organizations, exploitation of CVE-2025-67526 could result in severe consequences including unauthorized access to sensitive data, defacement or disruption of websites, and potential lateral movement within internal networks. Organizations relying on the ThimPress Sailing theme for their WordPress sites—commonly used for corporate, e-commerce, and informational portals—face risks to their brand reputation and customer trust. The vulnerability's ability to execute arbitrary code remotely without authentication means attackers can deploy web shells, ransomware, or steal credentials. This could lead to regulatory non-compliance issues under GDPR due to data breaches. Additionally, critical infrastructure or government websites using this theme could be targeted for espionage or sabotage. The widespread use of WordPress in Europe, combined with the popularity of the Sailing theme in certain markets, amplifies the threat. The absence of known exploits currently provides a window for proactive defense, but the high severity score indicates that any successful exploitation would have devastating effects.

1. Immediately update the ThimPress Sailing theme to version 4.4.6 or later once available, as this will contain the official patch addressing the vulnerability. 2. Until a patch is released, disable or restrict any functionality that allows dynamic inclusion of files via user input. 3. Implement strict input validation and sanitization on any parameters controlling file paths to prevent injection of remote URLs. 4. Configure web application firewalls (WAFs) to detect and block attempts to include remote files or suspicious URL patterns in requests. 5. Employ PHP configuration directives such as 'allow_url_include=Off' to prevent inclusion of remote files at the interpreter level. 6. Conduct thorough security audits and code reviews focusing on file inclusion logic in custom plugins or themes. 7. Monitor web server logs for unusual requests containing suspicious parameters or external URLs. 8. Use Content Security Policy (CSP) headers to restrict sources of executable scripts. 9. Educate site administrators about the risks and signs of compromise related to RFI attacks. 10. Consider isolating WordPress instances in containerized or sandboxed environments to limit impact of potential exploitation.