CVE-2026-28023 is a vulnerability classified as Improper Control of Filename for Include/Require Statement in the PHP program ThemeREX Nuts, specifically affecting versions up to 1.10. This vulnerability enables Remote File Inclusion (RFI), where an attacker can manipulate the filename parameter used in PHP's include or require statements to load arbitrary files from remote locations. This occurs because the application fails to properly validate or sanitize the input controlling the file path, allowing an attacker to specify a malicious URL or file path. When exploited, this can lead to remote code execution on the server, allowing attackers to run arbitrary PHP code, potentially leading to full system compromise. The vulnerability affects PHP-based web applications using the ThemeREX Nuts component, commonly found in WordPress themes or plugins. Although no known exploits are currently reported in the wild, the nature of RFI vulnerabilities makes them highly attractive targets. The vulnerability was reserved on February 25, 2026, and published on March 5, 2026, but no CVSS score has been assigned yet. The lack of authentication requirement and the direct impact on code execution make this a critical security issue for affected installations.

The impact of CVE-2026-28023 is significant for organizations using the ThemeREX Nuts PHP component. Successful exploitation can lead to remote code execution, allowing attackers to execute arbitrary commands on the affected server. This can result in data breaches, defacement of websites, installation of backdoors or malware, and disruption of services. Confidentiality is compromised as attackers may access sensitive data stored on the server. Integrity is at risk due to potential unauthorized modification of files and data. Availability can be affected if attackers disrupt services or deploy ransomware. Since the vulnerability does not require authentication, any attacker with network access to the vulnerable web application can attempt exploitation. This broadens the attack surface and increases the likelihood of compromise. Organizations relying on ThemeREX Nuts for their web presence or business-critical applications face increased risk, especially if they have not applied patches or mitigations.

To mitigate CVE-2026-28023, organizations should immediately check for updates or patches from ThemeREX addressing this vulnerability and apply them promptly. If no official patch is available, implement input validation and sanitization on all parameters controlling file inclusion to restrict allowed file paths strictly to trusted directories. Disable remote file inclusion in PHP configurations by setting 'allow_url_include' to 'Off' and 'allow_url_fopen' to 'Off' where feasible. Employ Web Application Firewalls (WAFs) to detect and block suspicious requests attempting to exploit file inclusion vulnerabilities. Conduct thorough code reviews of customizations involving include/require statements to ensure no user-controlled input is used directly. Monitor web server logs for unusual requests targeting file inclusion parameters. Isolate the affected application in a segmented network environment to limit potential lateral movement in case of compromise. Regularly back up website data and configurations to enable recovery from potential attacks. Finally, educate development teams on secure coding practices to prevent similar vulnerabilities.