CVE-2025-66216 is a heap buffer overflow vulnerability identified in the AIS-catcher software, a multi-platform AIS (Automatic Identification System) receiver used for maritime vessel tracking. The vulnerability resides in the AIS::Message class, where an incorrect calculation of buffer size (CWE-131) allows an attacker to write approximately 1KB of arbitrary data into a buffer that is only 128 bytes in size. This discrepancy leads to a heap overflow condition that can corrupt adjacent memory, potentially enabling remote attackers to execute arbitrary code, cause denial of service, or crash the application. The vulnerability is exploitable remotely without requiring authentication or user interaction, increasing its risk profile. AIS-catcher versions prior to 0.64 are affected, and the issue was patched in version 0.64. The CVSS 4.0 vector indicates network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), and high impact on confidentiality, integrity, and availability (VC:H/VI:H/VA:H). No known exploits are currently reported in the wild, but the critical severity score of 9.3 highlights the urgency of remediation. The vulnerability's root cause is improper buffer size calculation leading to heap overflow, a common and dangerous memory safety flaw.

For European organizations, this vulnerability poses a significant threat to maritime infrastructure, including port authorities, shipping companies, and maritime security agencies that rely on AIS-catcher for vessel tracking and situational awareness. Exploitation could lead to unauthorized code execution on systems processing AIS data, potentially disrupting maritime traffic monitoring, compromising sensitive operational data, or enabling attackers to pivot into broader network environments. The impact extends to safety-critical maritime operations and national security, given the strategic importance of maritime logistics in Europe. Disruption or manipulation of AIS data could also affect regulatory compliance and incident response capabilities. The vulnerability's remote exploitability and lack of required authentication increase the risk of widespread attacks if unpatched systems are exposed to the internet or untrusted networks.

1. Immediately upgrade AIS-catcher to version 0.64 or later, where the vulnerability is patched. 2. Implement network segmentation and restrict AIS-catcher system access to trusted networks only, minimizing exposure to untrusted sources. 3. Employ application-layer firewalls or intrusion detection systems to monitor and block anomalous AIS message traffic that could exploit buffer overflow conditions. 4. Conduct thorough input validation and sanitization on AIS message data before processing to prevent malformed inputs from triggering memory corruption. 5. Regularly audit and update maritime operational software to ensure timely application of security patches. 6. Establish incident response procedures specific to maritime system compromises to quickly detect and mitigate exploitation attempts. 7. Engage with AIS-catcher developers or community to stay informed about any emerging exploit techniques or additional patches.