CVE-2025-46001 is a critical arbitrary file upload vulnerability identified in the is_allowed_file_type() function of Filemanager version 2.3.0. This vulnerability stems from improper validation of uploaded files, allowing an attacker to bypass file type restrictions and upload malicious files, specifically crafted PHP scripts. Once uploaded, these malicious PHP files can be executed on the server, enabling remote code execution (RCE). The vulnerability is classified under CWE-434 (Unrestricted Upload of File with Dangerous Type), indicating that the application fails to properly restrict the types of files that can be uploaded. The CVSS v3.1 base score is 9.8, reflecting its critical severity with attack vector being network (AV:N), no privileges required (PR:N), no user interaction needed (UI:N), and impacts confidentiality, integrity, and availability at a high level (C:H/I:H/A:H). This means an unauthenticated attacker can remotely exploit this vulnerability without any user interaction, leading to full system compromise. The vulnerability was published on July 18, 2025, and no known exploits have been reported in the wild yet. However, given the severity and ease of exploitation, it is highly likely that threat actors will develop exploits rapidly. The lack of patch links suggests that no official fix has been released at the time of this report, increasing the urgency for mitigation.

For European organizations using Filemanager v2.3.0, this vulnerability poses a significant risk. Successful exploitation can lead to complete system compromise, allowing attackers to execute arbitrary code, steal sensitive data, disrupt services, or use compromised servers as pivot points for further attacks. This can affect confidentiality (data breaches), integrity (unauthorized data modification), and availability (service disruption or denial). Organizations in sectors such as finance, healthcare, government, and critical infrastructure are particularly at risk due to the sensitive nature of their data and services. Additionally, the ability to execute code remotely without authentication makes this vulnerability attractive for automated attacks and worm-like propagation. The absence of a patch increases exposure time, and organizations relying on Filemanager for file handling in web applications must prioritize risk assessment and mitigation. Regulatory compliance under GDPR may also be impacted if data breaches occur due to exploitation, potentially leading to legal and financial penalties.

1. Immediate mitigation should include disabling or restricting file upload functionality in Filemanager v2.3.0 until a patch is available. 2. Implement strict server-side validation of uploaded files, including checking MIME types, file extensions, and file content signatures to ensure only allowed file types are accepted. 3. Employ web application firewalls (WAFs) with rules to detect and block attempts to upload PHP or other executable files. 4. Restrict execution permissions on directories used for file uploads to prevent execution of uploaded scripts. 5. Monitor logs for suspicious upload attempts and anomalous file executions. 6. If possible, isolate the Filemanager application in a sandboxed environment or container to limit potential damage. 7. Regularly update and patch Filemanager once an official fix is released. 8. Conduct security audits and penetration testing focused on file upload mechanisms. 9. Educate developers and administrators about secure file upload practices to prevent similar vulnerabilities.