CVE-2025-4382 is a vulnerability affecting systems that use LUKS (Linux Unified Key Setup) encrypted disks combined with GRUB (GRand Unified Bootloader) configured for TPM (Trusted Platform Module)-based auto-decryption. In this setup, GRUB automatically decrypts the disk by retrieving the decryption key stored securely in the TPM and loading it into system memory during boot. The vulnerability arises when an attacker with physical access corrupts the filesystem superblock on the encrypted disk. This corruption causes GRUB to fail to locate a valid filesystem and enter its rescue mode. Critically, at this point, the disk has already been decrypted and the decryption key remains resident in system memory. Consequently, the attacker can access unencrypted data without any further authentication, bypassing the intended security controls. This flaw compromises data confidentiality directly. Additionally, since the attacker can induce this state by corrupting the filesystem, it also raises concerns about data integrity, as the attacker can manipulate the system state to cause unexpected behavior. The vulnerability has a CVSS v3.1 base score of 5.9 (medium severity), reflecting that exploitation requires physical access (AV:P), low attack complexity (AC:L), and privileges (PR:L), but no user interaction (UI:N). The impact on confidentiality and integrity is high, while availability is not affected. No known exploits are currently reported in the wild. The affected product is Red Hat Enterprise Linux 10, which is widely used in enterprise environments. This vulnerability highlights a critical gap in authentication for a sensitive function—disk decryption—when relying on TPM-based auto-decryption with GRUB, emphasizing the need for additional safeguards to prevent unauthorized physical access and filesystem tampering.

For European organizations, this vulnerability poses a significant risk to the confidentiality and integrity of sensitive data stored on LUKS-encrypted disks using TPM-based auto-decryption. Organizations relying on Red Hat Enterprise Linux 10 in sectors such as finance, healthcare, government, and critical infrastructure could face data breaches if an attacker gains physical access to affected machines. The ability to bypass authentication and access decrypted data directly undermines the trust in hardware-based security mechanisms like TPM. This could lead to exposure of personal data protected under GDPR, resulting in regulatory penalties and reputational damage. Furthermore, the integrity concerns mean attackers could manipulate system states or data, potentially disrupting business operations or causing erroneous processing. The requirement for physical access limits remote exploitation but increases the threat from insider attacks, theft, or unauthorized physical access to devices in offices, data centers, or remote locations. Given the widespread use of Red Hat Enterprise Linux in European enterprises, the impact could be broad, especially where TPM-based auto-decryption is deployed to streamline secure boot and disk encryption processes.

To mitigate this vulnerability, European organizations should implement the following specific measures: 1) Disable TPM-based auto-decryption in GRUB where possible, requiring manual authentication (e.g., passphrase entry) during boot to ensure that decryption keys are not loaded automatically into memory without user verification. 2) Implement strict physical security controls to prevent unauthorized physical access to systems, including secure server rooms, locked cabinets, and surveillance. 3) Regularly monitor and verify filesystem integrity using tools such as fsck or integrity monitoring solutions to detect and respond to superblock corruption attempts promptly. 4) Employ full disk encryption solutions that incorporate additional authentication layers or hardware protections beyond TPM auto-decryption, such as multi-factor authentication at boot. 5) Keep Red Hat Enterprise Linux systems updated with the latest patches and security advisories from Red Hat, as a patch addressing this vulnerability may be released. 6) Conduct security awareness training for staff to recognize and report suspicious physical access or tampering. 7) Consider using hardware security modules or alternative bootloaders that provide stronger authentication guarantees. These targeted steps go beyond generic advice by focusing on the specific attack vector involving TPM-based auto-decryption and filesystem corruption.