CVE-2025-39526 is a Local File Inclusion (LFI) vulnerability found in the nicdark Hotel Booking PHP application, affecting versions up to 3.6. The vulnerability stems from improper control over the filename parameter used in PHP's include or require statements, which allows an attacker to manipulate the input to include arbitrary files from the server's filesystem. This can lead to disclosure of sensitive files such as configuration files, password stores, or application source code. In some cases, if combined with other vulnerabilities or misconfigurations, it may allow remote code execution by including files containing malicious PHP code. The vulnerability is categorized as an improper control of filename for include/require statements, a common PHP security issue when user input is not properly sanitized or validated. No official patch or fix links are currently available, and no CVSS score has been assigned yet. There are no known exploits in the wild, but the vulnerability is publicly disclosed and should be considered a significant risk. Attackers exploiting this flaw do not necessarily require authentication, and exploitation can be performed remotely by sending crafted requests to the affected application. The nicdark Hotel Booking system is a PHP-based web application used by hospitality businesses to manage reservations, making it a target for attackers seeking to compromise customer data or disrupt operations.

The impact of CVE-2025-39526 can be severe for organizations using the nicdark Hotel Booking system. Successful exploitation can lead to unauthorized disclosure of sensitive information such as server configuration files, database credentials, or user data, compromising confidentiality. In some scenarios, it may allow attackers to execute arbitrary code remotely, threatening system integrity and availability. This can result in data breaches, defacement of websites, or full server compromise. For hospitality businesses, this could mean exposure of customer personal and payment information, leading to reputational damage, regulatory penalties, and financial losses. The vulnerability also increases the attack surface for further exploitation, such as pivoting into internal networks or deploying ransomware. Since the software is web-facing and often integrated with payment and booking systems, the scope of affected systems can be broad within an organization. The ease of exploitation without authentication and no user interaction required further elevates the risk level.

To mitigate CVE-2025-39526, organizations should first check for official patches or updates from nicdark and apply them promptly once available. In the absence of patches, immediate steps include implementing strict input validation and sanitization on all parameters used in include or require statements to ensure only allowed filenames or paths are processed. Employ whitelisting approaches to restrict file inclusions to known safe directories. Disable remote file inclusion capabilities in PHP configuration by setting 'allow_url_include' to 'Off' and 'allow_url_fopen' to 'Off' if not required. Use web application firewalls (WAFs) to detect and block suspicious requests attempting to exploit file inclusion. Conduct thorough code reviews and security testing to identify similar vulnerabilities. Monitor server logs for unusual access patterns or errors related to file inclusion. Segregate web server privileges to limit the impact of a successful exploit. Finally, consider deploying runtime application self-protection (RASP) tools to detect and prevent exploitation attempts in real time.