CVE-2025-53899 is a vulnerability classified under CWE-941, which relates to an incorrectly specified destination in a communication channel within the Kiteworks Managed File Transfer (MFT) platform. Kiteworks MFT is designed to orchestrate end-to-end file transfer workflows, ensuring secure and reliable data movement. Prior to version 9.1.0, the back-end component of Kiteworks MFT improperly handles the specification of communication channel destinations. This misconfiguration allows an attacker who already possesses administrative privileges on the affected system to intercept upstream communications. Such interception can expose sensitive data in transit and enable the attacker to escalate their privileges further within the system. The vulnerability affects all Kiteworks MFT versions below 9.1.0 and has been addressed in the 9.1.0 release. The CVSS v3.1 base score of 7.2 indicates a high-severity issue, with an attack vector over the network (AV:N), low attack complexity (AC:L), requiring high privileges (PR:H), no user interaction (UI:N), unchanged scope (S:U), and high impact on confidentiality, integrity, and availability (C:H/I:H/A:H). No known exploits are currently reported in the wild, but the potential for privilege escalation and data interception makes this a critical concern for organizations relying on Kiteworks MFT for secure file transfers.

For European organizations, the impact of CVE-2025-53899 is significant due to the critical role Kiteworks MFT plays in secure file transfer workflows, often involving sensitive or regulated data. Successful exploitation can lead to interception of confidential data, undermining data privacy and compliance with regulations such as GDPR. The escalation of privileges could allow attackers to manipulate or disrupt file transfer operations, potentially causing data integrity issues or denial of service. This can affect sectors with high data sensitivity, including finance, healthcare, government, and critical infrastructure. The breach of confidentiality and integrity could result in reputational damage, regulatory penalties, and operational disruptions. Given the network-based attack vector and the requirement for administrative privileges, insider threats or compromised administrative accounts pose the greatest risk. The absence of known exploits in the wild provides a window for proactive mitigation, but organizations must act swiftly to prevent exploitation.

1. Upgrade all Kiteworks MFT instances to version 9.1.0 or later immediately to apply the official patch addressing the vulnerability. 2. Enforce strict access controls and multi-factor authentication (MFA) for all administrative accounts to reduce the risk of privilege misuse or compromise. 3. Implement network segmentation to isolate Kiteworks MFT servers from less trusted network zones, limiting the attack surface. 4. Monitor network traffic and communication channels associated with Kiteworks MFT for unusual patterns or unauthorized interception attempts. 5. Conduct regular audits of administrative activities and system logs to detect potential misuse or early signs of exploitation. 6. Educate system administrators about the risks of this vulnerability and the importance of maintaining secure configurations. 7. Consider deploying intrusion detection/prevention systems (IDS/IPS) tailored to detect anomalies in file transfer workflows. 8. Review and update incident response plans to include scenarios involving compromised file transfer systems and privilege escalation attacks.