CVE-2024-38441 is a critical vulnerability identified in Netatalk, an open-source implementation of the Apple Filing Protocol (AFP) used primarily on Unix-like systems to provide file sharing services to macOS clients. The vulnerability arises from an off-by-one error in the FPMapName function within the afp_mapname routine in the directory.c source file. Specifically, the code incorrectly sets a null terminator at ibuf[len], which is just beyond the allocated buffer boundary, leading to a heap-based buffer overflow (CWE-193). This memory corruption flaw can be exploited remotely without any authentication or user interaction, as the AFP service typically listens on network ports accessible to clients. The buffer overflow allows an attacker to overwrite adjacent heap memory, potentially enabling arbitrary code execution, denial of service, or other malicious activities. The vulnerability affects all Netatalk versions prior to 3.2.1, with fixes also present in versions 2.4.1 and 3.1.19. The CVSS v3.1 base score is 9.8, reflecting the critical nature of the flaw with network attack vector, low attack complexity, no privileges required, and no user interaction needed. Although no exploits have been publicly reported yet, the vulnerability’s characteristics make it a prime target for attackers seeking to compromise AFP servers remotely. Organizations relying on Netatalk for AFP file sharing should prioritize upgrading to patched versions to mitigate this risk.

For European organizations, the impact of CVE-2024-38441 can be severe. The vulnerability allows remote attackers to execute arbitrary code on affected Netatalk servers, potentially leading to full system compromise. This threatens the confidentiality of sensitive files shared over AFP, the integrity of data stored on these servers, and the availability of file sharing services critical to business operations. Industries relying on macOS clients and Unix-based file servers, such as creative agencies, software development firms, and educational institutions, may face significant disruption. Additionally, compromised servers could be leveraged as footholds for lateral movement within corporate networks, increasing the risk of broader breaches. Given the critical CVSS score and the lack of required authentication, the vulnerability poses a high risk of exploitation, especially if AFP services are exposed to untrusted networks. European data protection regulations, including GDPR, heighten the consequences of data breaches resulting from such vulnerabilities, potentially leading to regulatory penalties and reputational damage.

To mitigate CVE-2024-38441, European organizations should immediately upgrade Netatalk installations to version 3.2.1 or later, or apply backported patches available in versions 2.4.1 and 3.1.19. Where immediate patching is not feasible, organizations should restrict AFP service exposure by implementing network segmentation and firewall rules to limit access to trusted hosts only. Disabling AFP services on systems where it is not required can reduce the attack surface. Monitoring network traffic for unusual AFP activity and deploying intrusion detection systems capable of recognizing exploitation attempts can provide early warning. Additionally, organizations should review and harden system configurations, including applying least privilege principles to AFP service accounts and ensuring secure coding practices in custom AFP extensions or scripts. Regular vulnerability scanning and penetration testing focused on AFP services will help identify residual risks. Finally, maintaining up-to-date backups is essential to recover from potential compromises.