CVE-2024-12747 is a race condition vulnerability discovered in the widely used file synchronization tool rsync. The flaw arises from improper synchronization when rsync processes symbolic links during file transfers. By default, rsync skips symbolic links to avoid unintended traversal. However, an attacker with the ability to manipulate files during the synchronization process can replace a regular file with a symbolic link at a precise moment, causing rsync to follow the symbolic link unexpectedly. This behavior can lead to unauthorized disclosure of sensitive information if the symbolic link points to protected files. Furthermore, if rsync is running with elevated privileges, this information leak could be leveraged to escalate privileges on the affected system. The vulnerability has a CVSS 3.1 base score of 5.6, indicating medium severity. The attack vector is local (AV:L), requiring the attacker to have low privileges (PR:L) and high attack complexity (AC:H), but no user interaction is needed (UI:N). The scope is changed (S:C), meaning the vulnerability can affect resources beyond the initially vulnerable component. No known exploits have been reported in the wild yet, but the presence of this race condition warrants caution, especially in environments where rsync is used for critical file synchronization tasks. The vulnerability was reserved in December 2024 and published in January 2025. No official patches or vendor advisories are listed yet, so organizations should monitor for updates.

For European organizations, the impact of CVE-2024-12747 depends largely on how rsync is deployed and the privileges under which it operates. Organizations using rsync on servers that handle sensitive data or run with elevated privileges are at risk of sensitive information leakage. This could include intellectual property, personal data protected under GDPR, or system configuration files. The potential for privilege escalation increases the risk profile, as attackers could gain higher-level access to systems, leading to broader compromise. Industries such as finance, healthcare, government, and critical infrastructure, which often rely on Linux-based systems and rsync for backup and synchronization, could face significant operational and compliance risks. The medium severity rating reflects the need for caution but indicates that exploitation is not trivial, requiring local access and precise timing. However, the confidentiality impact is high, which is critical for data protection regulations in Europe. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially in targeted attacks or insider threat scenarios.

1. Monitor for and apply official patches or updates from rsync maintainers as soon as they become available. 2. Restrict rsync execution privileges by running it with the least privileges necessary, avoiding root or administrative accounts where possible. 3. Implement file system monitoring to detect rapid or suspicious changes to files and symbolic links in directories synchronized by rsync. 4. Use access controls and mandatory access control (MAC) frameworks like SELinux or AppArmor to limit rsync's ability to follow symbolic links or access sensitive files. 5. Where feasible, configure rsync to use options that explicitly control symbolic link handling (e.g., --copy-links or --safe-links) to reduce the risk of traversal. 6. Conduct regular security audits of systems running rsync, focusing on privilege configurations and file system integrity. 7. Educate system administrators about the risks of race conditions and symbolic link attacks to improve operational security practices. 8. Consider isolating rsync operations within containers or restricted environments to limit potential damage from exploitation.