CVE-2025-4181 is a buffer overflow vulnerability identified in PCMan FTP Server version 2.0.7, specifically within an unspecified functionality of the SEND Command Handler component. This vulnerability allows an attacker to remotely send crafted input to the FTP server, causing a buffer overflow condition. Buffer overflows occur when data exceeds the allocated buffer size, potentially overwriting adjacent memory and enabling arbitrary code execution or denial of service. The vulnerability requires no authentication or user interaction, and the attack vector is network-based (remote). The CVSS 4.0 base score is 6.9, indicating a medium severity level, with low impact on confidentiality, integrity, and availability individually, but collectively enough to warrant concern. The vulnerability is exploitable remotely without privileges, making it accessible to unauthenticated attackers. Although no public exploit is currently known to be actively used in the wild, the exploit details have been disclosed publicly, increasing the risk of exploitation by threat actors. The lack of a patch or mitigation from the vendor at the time of publication further elevates the risk. The vulnerability affects a specific version (2.0.7) of PCMan FTP Server, a product used for file transfer services, which is critical in many enterprise environments for data exchange and backup operations. Exploitation could lead to remote code execution or service disruption, impacting business continuity and potentially allowing attackers to gain foothold within affected networks.

For European organizations, the impact of this vulnerability can be significant, especially for those relying on PCMan FTP Server 2.0.7 for critical file transfer operations. Exploitation could lead to unauthorized remote code execution, enabling attackers to compromise server integrity, exfiltrate sensitive data, or disrupt availability of FTP services. This could affect sectors such as finance, manufacturing, healthcare, and government agencies where FTP servers are used for internal and external data exchanges. Given the remote, unauthenticated nature of the exploit, attackers could leverage this vulnerability to establish persistence or pivot within networks, increasing the risk of broader compromise. Additionally, disruption of FTP services could impact supply chain communications and data workflows, leading to operational delays and financial losses. The medium CVSS score reflects moderate but tangible risks to confidentiality, integrity, and availability, which European organizations must address promptly to avoid exploitation. The public disclosure of exploit details increases the urgency for mitigation to prevent opportunistic attacks.

1. Immediate mitigation should include disabling or restricting access to PCMan FTP Server 2.0.7 instances until a vendor patch or update is available. 2. Network-level controls such as firewall rules should be implemented to restrict FTP server access to trusted IP addresses and internal networks only, minimizing exposure to the internet. 3. Employ intrusion detection/prevention systems (IDS/IPS) with signatures or anomaly detection capable of identifying buffer overflow attempts targeting FTP services. 4. Monitor FTP server logs for unusual or malformed SEND command requests that could indicate exploitation attempts. 5. Where possible, replace PCMan FTP Server 2.0.7 with alternative, actively maintained FTP server software that has no known vulnerabilities. 6. Implement network segmentation to isolate FTP servers from critical infrastructure and sensitive data repositories, limiting lateral movement in case of compromise. 7. Conduct regular vulnerability scans and penetration tests to detect vulnerable instances and verify mitigation effectiveness. 8. Prepare incident response plans specific to FTP server compromise scenarios to enable rapid containment and recovery. These steps go beyond generic advice by focusing on access restriction, monitoring for specific exploit vectors, and architectural controls to reduce risk exposure.