CVE-2025-13574 identifies an unrestricted file upload vulnerability in the Online Bidding System 1.0 developed by code-projects. The flaw exists in the categoryadd function within the /administrator/addcategory.php script, where the catimage parameter is insufficiently validated, allowing an attacker to upload arbitrary files. This vulnerability can be exploited remotely but requires the attacker to have high-level privileges (e.g., administrative access) on the system. The lack of proper file type validation and sanitization enables an attacker to upload malicious files, potentially leading to remote code execution, defacement, or further compromise of the server hosting the bidding system. The CVSS 4.0 vector indicates network attack vector (AV:N), low attack complexity (AC:L), no authentication bypass (AT:N), but requires high privileges (PR:H), no user interaction (UI:N), and low impact on confidentiality, integrity, and availability (VC:L, VI:L, VA:L). Although no known exploits are currently observed in the wild, a public exploit is available, increasing the risk of exploitation. The vulnerability affects only version 1.0 of the product, which is likely an early or legacy release. The absence of patches or official remediation links suggests that organizations must implement compensating controls or upgrade to a fixed version once available.

For European organizations using code-projects Online Bidding System 1.0, this vulnerability poses a moderate risk. Successful exploitation could allow an attacker with administrative privileges to upload malicious files, potentially leading to remote code execution, data tampering, or service disruption. This could compromise the confidentiality of sensitive bidding data, integrity of auction processes, and availability of the platform. Given the nature of online bidding systems, such disruptions could result in financial losses, reputational damage, and legal consequences under European data protection regulations such as GDPR. The requirement for high privileges limits the attack surface to insiders or attackers who have already compromised administrative credentials, but the availability of a public exploit increases the urgency to address this issue. Organizations relying on this software for critical procurement or auction activities should consider this vulnerability a significant operational risk.

To mitigate CVE-2025-13574, European organizations should immediately restrict administrative access to trusted personnel and enforce strong authentication mechanisms such as multi-factor authentication to reduce the risk of privilege escalation. Implement strict server-side validation of uploaded files, including whitelisting allowed file types, verifying MIME types, and scanning uploads for malware. Employ web application firewalls (WAFs) to detect and block suspicious file upload attempts. Regularly monitor logs for unusual activity related to the /administrator/addcategory.php endpoint. If possible, upgrade to a patched or newer version of the Online Bidding System once available. In the absence of official patches, consider isolating the bidding system in a segmented network environment to limit potential damage. Conduct security awareness training for administrators to recognize phishing or credential theft attempts that could lead to privilege compromise.