CVE-2025-49507 is a critical security vulnerability classified under CWE-502, which pertains to the deserialization of untrusted data. This vulnerability affects LoftOcean's CozyStay product in versions prior to 1.7.1. Deserialization vulnerabilities occur when an application deserializes data from untrusted sources without sufficient validation or sanitization, allowing attackers to manipulate the serialized objects. In this case, the vulnerability enables object injection attacks, where maliciously crafted serialized data can be injected and deserialized by CozyStay, potentially leading to arbitrary code execution, privilege escalation, or complete system compromise. The CVSS v3.1 score of 9.8 (critical) reflects the high impact and ease of exploitation: the attack vector is network-based (AV:N), requires no privileges (PR:N), no user interaction (UI:N), and affects confidentiality, integrity, and availability (C:H/I:H/A:H). The vulnerability is exploitable remotely without authentication, making it highly dangerous. Although no known exploits are currently reported in the wild, the severity and nature of the flaw suggest that exploitation could lead to full system takeover or data breaches. CozyStay is a product by LoftOcean, and the vulnerability affects all versions before 1.7.1, indicating that users running older versions are at risk. The lack of available patches at the time of publication increases the urgency for mitigation and monitoring. Organizations using CozyStay should consider this vulnerability a critical threat to their security posture.

For European organizations, the impact of CVE-2025-49507 could be severe. CozyStay is likely used in hospitality, accommodation management, or related sectors, which handle sensitive customer data including personal identification and payment information. Exploitation could lead to unauthorized access to this data, resulting in privacy violations under GDPR and potential financial penalties. Additionally, attackers could disrupt service availability, causing operational downtime and reputational damage. Given the criticality and remote exploitability, attackers could leverage this vulnerability to establish persistent footholds within networks, potentially moving laterally to other systems. This risk is heightened in organizations with less mature patch management or those that rely heavily on CozyStay for core business functions. The breach of confidentiality, integrity, and availability could also impact compliance with European cybersecurity regulations such as NIS2. The absence of known exploits currently provides a window for proactive defense, but the high severity demands immediate attention to prevent future attacks.

1. Immediate upgrade to CozyStay version 1.7.1 or later once available, as this version addresses the vulnerability. 2. Until patching is possible, implement network-level controls to restrict access to CozyStay services, such as IP whitelisting or VPN-only access, to reduce exposure to untrusted networks. 3. Employ Web Application Firewalls (WAFs) with custom rules to detect and block suspicious serialized payloads or unusual traffic patterns targeting deserialization endpoints. 4. Conduct thorough input validation and sanitization on any data deserialized by CozyStay, if customization or internal development is possible. 5. Monitor logs and network traffic for anomalies indicative of exploitation attempts, including unexpected serialized object data or unusual system behavior. 6. Implement strict segmentation of CozyStay servers from critical infrastructure to limit lateral movement in case of compromise. 7. Educate IT and security teams about the risks of deserialization vulnerabilities and ensure rapid response plans are in place. 8. Review and enhance backup and recovery procedures to mitigate potential data loss or ransomware scenarios stemming from exploitation.