CVE-2025-61662 is a Use-After-Free vulnerability identified in the gettext module of GNU grub2, a widely used bootloader in Linux-based systems. The root cause is a programming error where the gettext command remains registered in memory after its associated module has been unloaded. This orphaned command can be invoked by an attacker, causing the application to dereference a memory location that has already been freed. The consequence of this memory corruption is a crash of grub2, leading to a Denial of Service (DoS) condition during system boot. While the primary impact is availability disruption, the possibility of data confidentiality or integrity compromise cannot be fully excluded due to the nature of memory corruption vulnerabilities. The vulnerability has a CVSS v3.1 base score of 4.9, reflecting medium severity. The attack vector is local (AV:L), with high attack complexity (AC:H), requiring no privileges (PR:N) or user interaction (UI:N). This means an attacker must have local access to the system but does not need elevated privileges or user interaction to trigger the flaw. No public exploits or active exploitation in the wild have been reported to date. The vulnerability is cataloged under CWE-416 (Use-After-Free). Since grub2 is critical for system boot, exploitation can prevent affected systems from booting properly, causing operational disruptions. The affected versions are not explicitly detailed beyond '0', but it is implied that current versions at the time of publication are vulnerable. No patches have been linked yet, indicating that remediation may still be pending or in progress.

For European organizations, the primary impact of CVE-2025-61662 is the potential for Denial of Service during system boot, which can cause downtime and operational disruption. Organizations relying on Linux servers, workstations, or embedded devices that use grub2 as their bootloader are at risk. This includes critical infrastructure, government agencies, financial institutions, and enterprises with Linux-based environments. Although the vulnerability requires local access and has high attack complexity, insider threats or attackers who gain initial footholds could exploit it to disrupt system availability. The possibility of data confidentiality or integrity compromise, while not confirmed, raises concerns for sensitive environments. Systems that cannot boot due to grub2 crashes may require manual intervention, increasing recovery time and operational costs. The lack of known exploits reduces immediate risk but does not eliminate the threat, especially as patches are not yet available. Organizations with strict uptime requirements or those operating in regulated sectors may face compliance and service continuity challenges if affected systems become unavailable.

1. Monitor official GNU and Linux distribution security advisories closely for patches addressing CVE-2025-61662 and apply them promptly once released. 2. Restrict local access to systems using grub2 to trusted personnel only, minimizing the risk of local exploitation. 3. Implement strong access controls and auditing on Linux systems to detect unauthorized local access attempts. 4. For critical systems, consider implementing bootloader redundancy or recovery mechanisms to reduce downtime in case of grub2 failure. 5. Conduct regular backups of system configurations and critical data to facilitate recovery if systems become unbootable. 6. Use security tools to monitor for unusual system boot failures or crashes that could indicate exploitation attempts. 7. Educate system administrators about this vulnerability and the importance of limiting local access and promptly applying updates. 8. Evaluate the use of secure boot mechanisms and firmware protections that may mitigate bootloader tampering or exploitation. 9. In environments with high security requirements, consider isolating systems to reduce the risk of local attacker presence. 10. Engage with Linux distribution vendors to obtain timely patches and guidance specific to their grub2 implementations.