CVE-2025-0622 is a use-after-free vulnerability discovered in the GRUB2 bootloader, specifically within the command/gpg component. The issue arises because hooks created by dynamically loaded modules are not properly removed when the module is unloaded. This results in GRUB2 calling hooks that reference freed memory, leading to a use-after-free condition. An attacker with local high privileges can exploit this flaw to execute arbitrary code during the boot process. This can allow bypassing secure boot protections, which are designed to ensure only trusted code runs at system startup. The vulnerability requires local access with high privileges and does not require user interaction, but the attack complexity is high due to the need for precise timing and conditions. The CVSS v3.1 score is 6.4 (medium severity), reflecting the high impact on confidentiality, integrity, and availability if exploited, but mitigated by the requirement for local privileged access and high attack complexity. No public exploits are currently known, but the vulnerability poses a significant risk to systems relying on GRUB2, especially in environments where secure boot is critical for security assurance.

If exploited, this vulnerability can lead to arbitrary code execution at the bootloader level, allowing attackers to bypass secure boot protections. This compromises the integrity of the boot process, potentially enabling persistent malware installation that is difficult to detect or remove. Confidentiality, integrity, and availability of affected systems can be severely impacted. Organizations running Linux or Unix-like systems with GRUB2 are at risk, particularly those that rely on secure boot for trusted boot chain verification. The attack requires local privileged access, so insider threats or attackers who have already gained elevated privileges pose the greatest risk. The ability to bypass secure boot can undermine endpoint security, affecting critical infrastructure, servers, and sensitive environments worldwide.

Organizations should monitor for patches or updates from GRUB2 maintainers and apply them promptly once available. Until patches are released, restrict local privileged access to trusted users only and implement strict access controls and monitoring to detect suspicious activity. Employ system integrity verification tools that can detect unauthorized changes to boot components. Consider using hardware-based root of trust mechanisms in addition to secure boot to provide layered protection. Regularly audit and harden boot configurations and ensure that modules loaded into GRUB2 are from trusted sources. In environments where secure boot is critical, consider additional endpoint protection solutions that can detect boot-level tampering. Maintain up-to-date backups and incident response plans to recover from potential compromise.