CVE-2025-4382: Grub2: grub allow access to encrypted device through cli once root device is unlocked via tpm
A flaw was found in systems utilizing LUKS-encrypted disks with GRUB configured for TPM-based auto-decryption. When GRUB is set to automatically decrypt disks using keys stored in the TPM, it reads the decryption key into system memory. If an attacker with physical access can corrupt the underlying filesystem superblock, GRUB will fail to locate a valid filesystem and enter rescue mode. At this point, the disk is already decrypted, and the decryption key remains loaded in system memory. This scenario may allow an attacker with physical access to access the unencrypted data without any further authentication, thereby compromising data confidentiality. Furthermore, the ability to force this state through filesystem corruption also presents a data integrity concern.
Other sources
When using encrypted LUKS devices as a disk being unlocked through a TPM device and grub fails to find a underlying filesytem, the boot manager will go into rescue mode and will still have the encryption key in memory. This allows an attacker with physical access to the target machine to access encrypted that through grub CLI which should not be accessible in this scenario.
— Red Hat
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2025-4382?
CVE-2025-4382 is regarded as a high severity vulnerability due to the potential for physical access attacks.
How do I fix CVE-2025-4382?
To mitigate CVE-2025-4382, it is recommended to disable TPM-based auto-decryption and utilize alternative encryption management strategies.
Who is affected by CVE-2025-4382?
CVE-2025-4382 affects systems using LUKS-encrypted disks with GNU GRUB configured for TPM-based auto-decryption.
What type of attack can exploit CVE-2025-4382?
CVE-2025-4382 can be exploited through physical access to the system, allowing an attacker to manipulate memory to retrieve decryption keys.
What does CVE-2025-4382 involve regarding encryption management?
CVE-2025-4382 involves a flaw in how GRUB handles TPM-stored keys during the auto-decryption of LUKS-encrypted disks.