CVE-2025-54771 is a use-after-free vulnerability identified in the GNU GRUB bootloader component of Red Hat Enterprise Linux 10. The flaw arises from the file-closing process improperly retaining a pointer to a file system structure after the file has been closed, resulting in an expired pointer dereference. This memory mismanagement can cause GRUB to crash, leading to a denial of service (DoS) condition during the boot process. While the primary impact is availability disruption, the vulnerability also raises concerns about potential data integrity or confidentiality compromise, although no direct evidence confirms such exploitation. The vulnerability requires local access to the system and has a high attack complexity, meaning an attacker must have significant privileges or conditions to exploit it. No user interaction is needed, and the scope is limited to the local system. The CVSS 3.1 base score is 4.9, reflecting medium severity with partial impacts on confidentiality, integrity, and availability. No known public exploits exist yet, and no patches have been linked at the time of publication. The vulnerability was reserved in July 2025 and published in November 2025, indicating recent discovery and disclosure.

For European organizations, the primary impact is the potential for denial of service during system boot, which can cause downtime and disrupt business operations, especially in environments relying on Red Hat Enterprise Linux 10 for critical infrastructure or enterprise servers. Although the vulnerability is local and requires high attack complexity, insider threats or attackers with local access could exploit it to cause system instability. The possible but unconfirmed risk to data confidentiality and integrity could have more severe consequences if further exploitation techniques are developed. Organizations in sectors such as finance, healthcare, government, and manufacturing, which often use Red Hat Enterprise Linux, may face operational disruptions. The downtime caused by bootloader crashes could affect availability of services and systems, leading to financial losses and reputational damage. The lack of known exploits reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits over time.

1. Restrict local access to systems running Red Hat Enterprise Linux 10 to trusted administrators only, minimizing the risk of exploitation by unauthorized users. 2. Monitor system logs and boot processes for unusual crashes or instability that could indicate attempted exploitation of this vulnerability. 3. Implement strict privilege management and auditing to detect and prevent unauthorized local access. 4. Prepare for rapid deployment of patches or updates from Red Hat once they become available; subscribe to Red Hat security advisories to stay informed. 5. Consider implementing bootloader integrity verification mechanisms and secure boot features to detect tampering or corruption. 6. In virtualized or containerized environments, isolate critical systems to reduce the impact of potential DoS conditions. 7. Conduct regular backups and disaster recovery drills to mitigate the impact of potential system unavailability. 8. Evaluate and update incident response plans to include scenarios involving bootloader vulnerabilities and local denial of service attacks.