CVE-2025-15495 is a vulnerability identified in BiggiDroid Simple PHP CMS version 1.0, specifically within the /admin/editsite.php file. The vulnerability arises from improper handling of the 'image' parameter, which allows an authenticated user with high privileges to perform unrestricted file uploads. This flaw enables attackers to upload arbitrary files, including potentially malicious scripts, without any validation or restriction. Because the vulnerability is located in an administrative interface, exploitation requires authenticated access with elevated privileges, but no user interaction beyond that is necessary. The vulnerability has a CVSS 4.0 base score of 5.1, indicating medium severity, with attack vector being network-based and low complexity. The vendor was contacted but did not respond, and no official patches or mitigations have been released. Public exploit code has been made available, increasing the risk of exploitation. The unrestricted upload can lead to remote code execution, defacement, or further compromise of the affected system. The lack of vendor response and patch availability means organizations must rely on compensating controls to mitigate risk. The vulnerability impacts confidentiality, integrity, and availability due to the potential for arbitrary code execution and system compromise.

For European organizations, this vulnerability poses a significant risk especially to those using BiggiDroid Simple PHP CMS 1.0 for their websites or internal portals. Successful exploitation could lead to unauthorized code execution, data breaches, website defacement, or use of the compromised server as a pivot point for further attacks. Given the administrative nature of the vulnerable script, attackers must first gain high-level credentials, which may be obtained through phishing or credential theft. The impact on confidentiality is moderate due to potential data exposure, integrity is high as attackers can alter site content or upload malicious code, and availability could be disrupted by malicious payloads or defacement. Organizations in sectors with public-facing web services, such as media, education, or small businesses, are particularly vulnerable. The absence of vendor patches increases exposure duration, and the availability of public exploits raises the likelihood of attacks. Additionally, compliance with European data protection regulations (e.g., GDPR) could be jeopardized if sensitive data is compromised.

1. Immediately restrict access to the /admin/editsite.php endpoint to trusted IP addresses or VPN users only. 2. Implement strict authentication and multi-factor authentication (MFA) for all administrative accounts to reduce the risk of credential compromise. 3. Employ web application firewalls (WAFs) with rules to detect and block suspicious file upload attempts targeting the image parameter. 4. Conduct thorough input validation and enforce file type and size restrictions on uploads, ideally allowing only specific image MIME types and scanning uploads for malicious content. 5. Monitor server logs and web traffic for unusual activity related to file uploads or administrative access. 6. If possible, isolate the CMS environment in a sandbox or container to limit the impact of a potential compromise. 7. Regularly back up website data and configurations to enable rapid recovery in case of defacement or compromise. 8. Engage in active threat hunting to detect signs of exploitation attempts. 9. Consider migrating to a more actively maintained CMS platform or applying custom patches if feasible. 10. Stay informed about any future vendor updates or community patches addressing this vulnerability.