LUKS (Linux Unified Key Setup) is the standard disk-encryption format used on many Linux systems. It encrypts a block device and stores metadata in a volume header, including keyslots, cipher settings, and the information needed to unlock the data. The data itself stays unreadable without the correct passphrase, recovery key, or hardware-backed unlock token.
In cybersecurity, LUKS matters because it protects data at rest on laptops, servers, and thin clients. It is often paired with TPM-based measured boot, so the system can release the unlock key only if startup measurements look trusted. Real attacks usually target the boot path, key management, or exposed metadata rather than breaking LUKS encryption itself. Defenders harden LUKS with strong passphrases, recovery procedures, Secure Boot, and strict control of early boot files.